Learning Outcomes, Motivation, and Satisfaction in Gamified English Vocabulary Learning

The past several years have been witnessing the fast development of information and communication technology, with which an increasing number of serious games are being designed and developed. Randomly selected participants were divided into the treatment and control cohorts. Two experiments, as well as a semi-structured interview, were administered to both cohorts. It was concluded that: (1) Learning outcomes in gamified English vocabulary learning are significantly better than in non-gamified English vocabulary learning; (2) The motivation in gamified English vocabulary learning is significantly stronger than in non-gamified English vocabulary learning; (3) The satisfaction in gamified English vocabulary learning is significantly higher than in non-gamified English vocabulary learning. Future research could include various serious games with interdisciplinary cooperation to testify the effect of gamification on English vocabulary learning.


Introduction
The period ranging from the 1960s and the 1970s saw the increasing popularity of gamified learning, but gamified learning was dwarfed under the influence of Back to Basics teaching movement (Rice, 2007).The Back to Basics teaching movement began in the 1970s, aimed to turn the innovative pedagogy back to the non-gamified style due to the phenomenon that students performed poorly on standardized tests.The movement suggested that teaching be focused on non-gamified reading, writing, arithmetic, and other basic skills training.
The twentieth century has been witnessing the fast development of information and communication technology, with which an increasing number of serious games are being designed and developed.Serious games (Abt, 1970) indicated the games designed for education and other serious purposes such as industrial development, training, or stimulation (Alsawaier, 2018).Recently, numerous gamified English vocabulary learning mobile apps have been developed and applied to English vocabulary education.Examples are Baicizhan, Kingsoft, Hujiang Fun Vocabulary, New Oriental Fun Vocabulary, Kingsoft Powerword, Shanbei Vocabulary, Momo Vocabulary, Zhimi Vocabulary, Immersion Vocabulary, and virtual reality vocabulary learning games (Lai & Chen, 2021).Educators have attempted to integrate elements of serious gaming most of these mobile applications (Govender & Arnedo-Moreno, 2021), and installed them on mobile devices such as smartphones, PDAs, and iPods.Of them, the most popular one is Kingsoft Powerword.
Different from traditionally perceived games for entertainment, serious games aim to meet educational needs rather than entertaining aims (Nazry & Romano, 2017).The adjective ''serious'' is an umbrella term referring to video games designed for primary use in military defense, education, academic research, medical science, urban designing, international communication, cultural understanding, and political exchange.Serious games are deemed as gaming tools used for educational purposes, where game players are expected to obtain knowledge during the gameplay process.Through computer programs, players' performances could automatically be scored in the game (Juan et al., 2017).Task completion could render awards, such as scores, advancement, and power gain, to players.
Serious games have the features such as gamified mobility and flexibility through installation on mobile devices.Players can learn English vocabulary through gamified methods whenever or wherever they feel convenient.Gamified vocabulary learning tends to possess the attributes of competition, storytelling, achievements, curiosity, collaboration, fun, and entertainment.The attributes of gamified learning could influence English vocabulary acquisition.Relationships between gaming attributes and mechanics exerted a great influence on academic achievements and learning experiences (Lameras et al., 2017).
Serious games could promote the engagement of students in learning activities via their gamified features.The elements of entertainment and fun of gamification also attract game players to engage in learning through interesting gameplay (Yu, 2018).The ''serious'' conception explicitly sheds light on the extra pedagogical value except for fun and competition of games (Yu, 2019).Stimulated to play games, learners tend to be able to subconsciously acquire English linguistic knowledge through watching, reading, listening, and even speaking.
With the swift development of gaming designs, gamified learning also seems promising to play an important role in English vocabulary learning.However, the research into the effectiveness of gamified learning cannot keep pace with information technology development, especially in the field of English vocabulary acquisition (Yu, 2018).To promote the development of gamified vocabulary learning, related convincing studies are in need to strike a balance between the rapid development of information technology and gamified vocabulary learning.
Although an increasing number of gamified apps have been used in English vocabulary acquisition, scanty studies have been committed to their effect on vocabulary learning.One of the major trends in English vocabulary acquisition studies focuses on the effect of digital games on vocabulary acquisition (H.J. H. Chen & Hsu, 2020).This study, aiming to determine their effect on English vocabulary learning, is therefore meaningful and necessary.Precious studies have hardly identified the effect of gamification on learning outcomes, motivation, and satisfaction in gamified English vocabulary.This study will fill this research gap by both quantitatively and qualitatively examining its effects on English vocabulary learning outcomes, motivation, and satisfaction.

Theoretical Framework
Researchers defined a serious game, also referred to as learning games, games for learning, educational games, and training games (Landers, 2014), as ''a game in which education (in its various forms) is the primary goal, rather than entertainment'' (Michael & Chen, 2005, p. 17).It is hard to arrive at a consensus on the definition of a serious game (Klabbers, 2009).A solution lies in the exploration of attributes of gamified learning or a model to construct attributes of gamified learning.Wilson et al. (2009) synthesized nineteen attributes (Bedwell et al., 2012), which was then classified into nine categories, that is, action language, assessment, conflict/challenge, control, environment, game fiction, human interaction, immersion, and rules/goals (see Table 1).
Based on the nine attributes of gamified learning, Kingsoft Powerword assisted learning is considered gamified learning.Its use in English vocabulary learning is thus deemed as gamified English vocabulary learning since it consists of action language, assessment or evaluation, conflicts or challenge in learning process, control of learning steps, environment designed for learning, game fictions as learning materials, human interactions with the program, immersion environments, and rules or goals for learning and scoring.However, scanty studies have been committed to the effect of Kingsoft Powerword on learning outcomes, motivation, and satisfaction in gamified English vocabulary learning.This study is meaningful and worthwhile because it aims to fill this research gap.

Literature Review
This review of literature will be chronologically developed with a view to presenting a clear picture to readers.Various kinds of serious games, especially those designed for youngsters, surged up in the early 2000s, many of which were not used on the fixed desktops but installed on mobile devices.In the year 1999, LeapFrog Enterprises developed a serious game named LeapPad, which integrated an interactive book into a cartridge and allowed kids to play games.The company also developed a hand-held game in 2003, referred to as Leapster, aiming to meet educational needs by integrating cartridges into arcades (Gray et al., 2009).Gamified learning was connected to sustainable development in the 2000s, in association with subjects including Learning Sustainable Development in 2000, as well as Climate Challenge in 2006 (Katsaliaki & Mustafee, 2012).
The use of a serious game named ''Bingo'' was evidenced effective in sight word learning and reading (Kirby et al., 1981).A patented board serious game could meet participants' individual needs and improve the effectiveness of vocabulary acquisition (Burrowes, 2003).Another serious game referred to as ''The SIMS'' could also significantly improve English vocabulary learning although the sample was relatively small (Miller & Hegelheimer, 2006).The plentiful contexts, cognitive engagements, and virtual language learning situations in the gamified learning could also act as a stimulus to improve language learning effectiveness (Ranalli, 2008).
Several studies reported gamified English vocabulary learning effectiveness.Observers of gamified learning outperformed players in a computer science class in terms of vocabulary learning (Dehaan et al., 2010).The serious game observers could also recall significantly more English words than the players.Players held that gameplay was significantly more difficult than observation (Dehaan et al., 2010).Both game players and observers performed significantly better than those who learned English vocabulary through the non-gamified approach.Gamification could also positively influence English vocabulary learning of students at different levels of English proficiency (Peterson, 2010).Researchers explored the design of gaming elements (Deterding et al., 2011), psychological influence on gamified learning outcomes (Boyle et al., 2011), and learning outcomes in serious virtual environments (Wrzesien & Alcaniz Raya, 2010).
In 2012, the research interest of scholars was shifted to gamification at the workplace out of campus.A study also explored the factors that influenced gamification in the business settings, including instructional contents, game dimensions, game cycle, debriefing, perceived educational worth, acquired learning skills, and intrinsic motivation (Guille´n-Nieto & Aleson-Carbonell, 2012).Cognitive loads and academic achievements were considered important factors in gamification, where heavier cognitive loads could render poorer academic achievements, and vice versa (Cowley, Heikura, & Ravaja, 2013;Cowley, Ravaja, & Heikura, 2013).Gamification could significantly enlarge the range of vocabulary compared with non-gamified vocabulary learning methods such as hardcopy texts, lists of words, and multiple-choice questions (Smith et al., 2013).
The year 2014 witnessed some positive results of the use of gamification in learning.Gamification could improve learning outcomes in construction education in terms of theories and practice, where gamification proved useful and engaging.Compared with students who did not learn construction aided with gamification, those aided with gamification acquired significantly more procedural and declarative knowledge in the discipline (Dib & Adamo-Villani, 2014).The less time-consuming gamified vocabulary learning was significantly more effective than non-gamified English vocabulary learning approach without gamification (Sandberg et al., 2014).Satisfied with the gamified English vocabulary learning approach, they practiced English vocabulary learning adaptively Table 1.Nine Attributes of Gamified Learning (Bedwell et al., 2012).

Action language
The method and interface by which communication occurs between a player and the game itself To participate in an online learning activity, students are now required to use game console controllers (e.g., a PlayStation controller).

Assessment
The method by which accomplishment and game progress are tracked In a learning activity, points are used to track the number of correct answers obtained by each learner as each learner completes the activity.

Conflict/challenge
The problems faced by players, including both the nature and difficulty of those problems A small group discussion activity is augmented such that each small group competes for the ''best'' answer.

Control
The degree to which players are able to alter the game, and the degree to which the game alters itself in response A small group discussion activity is restructured such that each decision made by each small group influences the next topic that the group will discuss.

Environment
The representation of the physical surroundings of the player A class meeting is moved from a physical classroom to a 3D virtual world.

Game fiction
The fictional game world and story Lectures, tests, and discussions are renamed adventures, monsters, and councils, respectively.Human interaction The degree to which players interact with other players in both space and time Learners participate in an online system that reports on their assignment progress to other students as they work.

Immersion
The affective and perceptual experience of a game When learning about oceanography, the walls of the classroom are replaced with monitors displaying realtime images captured from the seafloor.

Rules/goals
Clearly defined rules, goals, and information on progress toward those goals, provided to the player When completing worksheet assignments on tablet computers, a progress bar is displayed to indicate how much of the assignment has been completed.
and independently, and believed they could extend the range of vocabulary and improve their language perceptions (Schamroth & Sara, 2014).Similarly, in 2015, gamification was also reported beneficial to education.Students held positive attitudes towards, and positive cognitive and affective perceptions of gamified education.Compared with quizzes and adventures, simulations significantly improved the comprehension and application of knowledge.Females possessed significantly higher understandings of negative feelings of gamification and also held significantly more positive attitudes toward gamification than males (Riemer & Schrader, 2015).A real-time analytical serious game was also positively assessed in terms of teaching goals and progress (Minovic et al., 2015).Gamification could facilitate reading comprehension, by which English vocabulary acquisition could be greatly improved (Sundqvist & Wikstro¨m, 2015).Gamification could also enhance the retention of English vocabulary so that the effectiveness of vocabulary learning was improved (Alshaiji, 2015).
The year 2016 also saw several studies in support of gamification in education.Gaming easiness and instruction played a significantly more important role than gaming enjoyment and motivation in the effect of gamification on learning outcomes (Iten & Petko, 2016).In case that the learning goals were clear and the serious game was easy to play, learners would concentrate on the gameplay to complete the task (Y.Wang et al., 2017).The vocabulary review game-assisted learning could facilitate English vocabulary learning significantly more than non-gamified English vocabulary learning approach without the assistance of gamification (Hassinger-Das et al., 2016).
Surprises in gaming could lead to learning effectiveness in terms of proportional reasoning skills (Wouters et al., 2016).Gamification could render significantly better academic achievements and encourage students to participate in academic activities because gamified pedagogy could provide flexible learning without limitations of time and space (Garneli et al., 2016).Gamified learning could improve effectiveness in social learning, which was especially favored by team opinions ( Van der Wal et al., 2016).Therefore, social engagement in the classroom should be seriously considered in the future gamified design (Bossavit & Parsons, 2018).
A recent study (Cheng et al., 2016) argued that serious game designers and educators should take into account several factors to achieve success in gamification.The factors included backstory and production, realism, artificial intelligence and adaptivity, interaction, and feedback and debriefing.The perceived usefulness of the game and the interactions also played important roles in the effective gamification (Malaquias et al., 2018).
Gamification could also increase players' cognitive abilities and enhance their positive learning effect (Lamb et al., 2018).
Gamification could improve recollection of vocabulary, and promote vocabulary transferability in authentic contexts, by which English vocabulary acquisition could be enhanced (Franciosi, 2017).Serious game players could facilitate vocabulary learning by using learning strategies, including repetitions of vocabulary, contextual inferences, convenient communication, and animated visualization in authentic situations (Ebrahimzadeh, 2017).The recollection and transferability could be indispensable abilities to enhance the range of vocabulary.Students who possess these abilities could organize the structures of vocabulary and practice them frequently, leading to improved vocabulary skills in different contexts.
Additionally, the interactivity of serious games could influence the vocabulary learning effectiveness to a large extent (Ebrahimzadeh & Alavi, 2016), as well as design features of gamification such as age and linguistic backgrounds (M.Chen et al., 2018).The interactivity-oriented serious game could significantly improve English vocabulary acquisition than the less interactive one and the latter could significantly facilitate English vocabulary acquisition than the non-gamified vocabulary acquisition (Yu, 2018).A reasonable amount of, rather than excessive or inadequate, player anxiety and mental effort could also improve the vocabulary learning effectiveness (Hsu, 2017;Khowaja & Salim, 2018).
Furthermore, another serious game, referred to as Vocabulary.com, could promisingly extend the range of vocabulary knowledge, although it did not lead to gains in highly risky test results (McGregor et al., 2019).Assisted with Persian-language word exercise games, phonological mistakes correction training could improve the spelling skills of students with dyslexia (Zare et al., 2020).Language and structural features, and featuring word games of Lewis Carroll were directly correlated with the cell/cell and cell/matrix recognition processes (Faria, 2020).The game features could improve the recognition of vocabulary, coupled with vocabulary acquisition.
However, there are still inconsistent findings of the effect of gamification on English vocabulary learning.It was found that students in the treatment group learned significantly less gaming knowledge than the control group when the latter experienced active learning (Sitzmann, 2011), while the opposite findings were revealed by Wouters et al. (2016) who concluded that gamification improved learning effectiveness significantly more than the passive instruction.Single-game player conditions failed to demonstrate significantly superior to non-game control conditions in terms of learning outcomes.Furthermore, no significant and consistent correlation between gameplay duration and learning effect was found although a proper, rather than a long, duration of gameplay might be effective in learning.It was argued that a single-player game might be more effective than collaborative gameplay.However, it was also concluded that the competitive single-player game was reported most ineffective (Clark et al., 2014).Gamification reportedly enhanced student motivation, instead of knowledge gain (Connolly et al., 2012), which was echoed by Boyle et al. (2016).Although the above findings are out of date, they still provide evidences against the effect of gamification on learning outcomes.

Research Questions and Hypotheses
Considering the inconsistent findings in the past research into gamification, learning outcomes, levels of motivation, and satisfaction of use of gamification remain controversial.The research questions in this study were therefore raised as: (1) Are learning outcomes in gamified English vocabulary learning significantly better than in non-gamified English vocabulary learning?(2) Is the motivation in gamified English vocabulary learning significantly stronger than in non-gamified English vocabulary learning?(3) Is the satisfaction in gamified English vocabulary learning significantly higher than in nongamified English vocabulary learning?
We raised three null hypotheses: (1) Learning outcomes in gamified English vocabulary learning are not significantly better than in non-gamified English vocabulary learning; (2) The motivation in gamified English vocabulary learning is not significantly stronger than in non-gamified English vocabulary learning; (3) The satisfaction in gamified English vocabulary learning is not significantly higher than in non-gamified English vocabulary learning.
The three alternative hypotheses are put forward as: (1) Learning outcomes in gamified English vocabulary learning are significantly better than in non-gamified English vocabulary learning; (2) The motivation in gamified English vocabulary learning is significantly stronger than in non-gamified English vocabulary learning; (3) The satisfaction in gamified English vocabulary learning is significantly higher than in non-gamified English vocabulary learning.

Research Methods
A quasi-experimental mixed design was adopted to determine the variables of motivation, satisfaction, and learning outcomes in both the gamified and non-gamified English vocabulary learning approaches.Two experiments were involved in the study, as well as a semi-structured interview.The former aims to collect quantitative data, while the latter aims to collect qualitative data.
In an experiment, an extraneous variable is any variable that researchers are not investigating that can potentially affect the outcomes of the research study.If left uncontrolled, extraneous variables can lead to inaccurate conclusions about the relationship between independent and dependent variables.Therefore, the same researchers conducted both experiments in the same classrooms to minimize the effect of extraneous variables.

Participants
In both experiments, all the participants, normal in literacy and psychology, agreed to participate in the experiments by signing the consent form.They were all informed that the obtained data would be merely used in this study and their personal information would remain confidential.All of them received proper rewards after they completed the corresponding tasks.
In the first experiment, participants were randomly selected from a public university located in Beijing, China, who were divided into two cohorts: Cohorts A and B. Cohort A (N = 35), where there were 6 males and 29 females, learned English vocabulary assisted with a gamified app-Kingsoft Powerword, while Cohort B (N = 36), where there were 5 males and 31 females, learned English vocabulary through non-gamified vocabulary learning approach.The age in both cohorts ranged from 18 to 21 (M = 20.10,SD = 0.943).The learning process endured for one semester.All the participants' ranges of English vocabulary were tested through pre-and post-vocabulary tests.
In the second experiment, the same participants as in the first experiment were all required to finish filling preand post-questionnaires aiming to determine levels of satisfaction and motivation of gamified English vocabulary learning.They were all informed that the obtained data would merely be used in the study and their personal information would remain confidential.They all agreed to participate in the study by signing the consent form.

Research Instruments
The research instruments used in this study include an English vocabulary test, a scale to identify the motivation level, and a scale to determine the satisfaction level.
The English Vocabulary Test.CET 4 has been evidenced reliable and valid to determine test-takers' vocabulary range since her birth in the year 1987 (B. A. Wang, 2004).The English vocabulary test, composed of thirty multiple-choice test items, was adapted from College Yu English Test Band Four (CET4).Each test item was made of a statement with one or more blanks, followed by four options.Test-takers were required to select an option to complete the statement.An example is ''The early pioneers had to ____ many hardships to settle on the new land.A. go into B. go through C. go back on D. go along with (June, 2000).''The correct answer is B. In case test-takers choose B, they will obtain 1 point.Otherwise, they will obtain 0 point.
The Scale to Identify the Motivation Level.The level of motivation will be identified based on self-efficacy and intrinsic value.The scale of self-efficacy, made of nine items, was revised on the basis of the Motivated Strategies for Learning Questionnaire (MSLQ) (Pintrich et al., 1991), followed by a 5-point Likert scale scoping from strongly disagree, disagree, unknown, agree, to strongly agree.Participants will obtain 1 point for choosing strongly disagree, 2 points for disagree, 3 points for unknown, 4 points for agree, and 5 points for strongly agree.MSLQ was evidenced internally reliable (.89 \ a \ .93;e.g., Pintrich et al., 1991).The intrinsic value scale was also revised based on MSLQ, which contained nine items, followed by a 5-point Likert Scale, ranging from strongly disagree, disagree, unknown, agree, to strongly agree.Participants will be scored based on the same method as in the scale of self-efficacy.
The Scale to Determine the Satisfaction Level.Levels of satisfaction are positively correlated with levels of interaction and self-regulation (Yu, 2015).This study, therefore, determines the level of satisfaction by integrating it into interaction and self-regulation.Three dimensions, that is, satisfaction, interaction, and self-regulation (Yu, 2015) were used to determine the level of satisfaction of gamified English vocabulary learning in this study.The satisfaction, interaction, and self-regulation scales are composed of seven, five, and four questions respectively.All the questions are followed by a 5-Likert scale, that is, strongly disagree, disagree, unknown, agree, and strongly agree.Participants will be scored based on the same method as in the scale of self-efficacy.
The Kingsoft Powerword.The Kingsoft Powerword, designed and produced by Kingsoft Software Company, supports mutual translation between many languages such as Chinese, English, French, Korean, Japanese, Spanish, and German.It has been frequently consulted by approximately 20 million users and 50,000 organizations.It can be installed on most electronic devices including mobile or handheld devices such as smartphones (both Android and iPhone versions), and iPods.It can also be installed on personal computers.It can help learners acquire foreign language words by providing vivid pictures, fun stories, dynamic and native listening materials, interesting videos, and bookstores where varieties of e-books are accessible (Hu & Lei, 2022).
Learners can also learn words by simply clicking ''word learning.''Then learners can access vast word banks.They can match words in different languages by connecting them, doing multiple choices, listening to radios and standard pronunciation, or doing dictations.They can also access various kinds of words for playing games such as Hero Union.When learning the gaming words, they can also use various methods such as radio listening, word matching, and word recollection through listening (Figure 1).
They can play games after learning related words, by which the acquired words may be stored in the mind for longer.They can also play games by joining the vocabulary test games, which contributes to rankings of final scores.The range of vocabulary can be obtained through vocabulary games, whose results are revealed to participants via rankings.In the match, game learners could match the words, pictures, explanations, or definitions to check if they are familiar with the meanings of the words.All of their learning behaviors will automatically be saved as references or reminders for their further learning.If they attempt to skip over a unit, an alert will instantly arrive for them to confirm the operation.Whenever they log in to the Kingsoft Powerword, they will receive a reward such as increased points, or heightened user level.Once they fail to log in, they will be warned.Learners can also select the favored system response by revising the settings.
A Semi-Structured Interview.The semi-structured interview is composed of three sections.The first section aims to collect demographic information including gender, age, and educational level.The second section, the major part, aims to collect data regarding the levels of motivation and satisfaction using questions from the questionnaires.The third section is the acknowledgment part, aiming to extend gratitude to interviewees.

Procedure
The procedure of the study flowed from the first experiment, the second experiment to the semi-structured interview (see Figure 2).
In the first experiment, both Cohorts A and B experienced pre-and post-vocabulary tests, with a period of a four-month semester.The pre-vocabulary test was administered in the first week of the semester, and the postvocabulary test was administered in the final week of the semester.During the semester, Cohort A learned English vocabulary aided with the Kingsoft Powerword, while Cohort B learned English vocabulary aided with printed dictionaries and paper materials instead of the Kingsoft Powerword.
In the second experiment, both Cohorts A and B were required to fill in pre-and post-questionnaires including scales to determine levels of both motivation and satisfaction.The pre-questionnaire was administered at the beginning of the semester, while the post-questionnaire was administered at the end of the semester.After both experiments, randomly selected voluntary participants  received interviews in a quiet room, which was recorded and transcribed for further analysis.
Two experienced researchers independently conducted and analyzed the interviews.The interview questions were adapted from the scales measuring learning outcomes, motivation, and satisfaction in gamified English vocabulary learning.Themes emerge from the interview data included the learning outcomes, satisfaction, and motivation in English vocabulary assisted with gamification methods.

Results
The results will be presented according to the sequence of research hypotheses put forward in this study.

Tests of Assumptions
The Kolmogorov-Smirnov and Shapiro-Wilk tests can be used to test whether the data are normally distributed.The results are shown in Table 2.
Kolmogorov-Smirnov and Shapiro-Wilk tests indicate that most data on vocabulary ranges, motivation, and satisfaction levels are not normally distributed at the significance level p = .05.Specifically, data from pre-and post-vocabulary tests, pre-motivation, pre-satisfaction in Cohort A, post-satisfaction in Cohort A are not normally distributed at the significance level p = .05.Other data are not consistently distributed, which is determined by both Kolmogorov-Smirnov and Shapiro-Wilk tests.

Results of Mann-Whitney U tests
Since the quantitative data obtained from pre-and postvocabulary tests and scales to determine both motivation and satisfaction levels are not normally distributed, a Mann-Whitney U test, which does not need a normal distribution of data, was thus conducted to test the null hypotheses.Another reason for use of the nonparametric test is that the collected data in this study also meet the assumptions: (1) The data are continuously distributed among the population; (2) The participants were randomly sampled from the populations, and the obtained data were mutually independent.Running a Mann-Whitney U test contributes to the data summarized in Table 3.
A Mann-Whitney U test was conducted to determine whether there were significant differences in prevocabulary tests, pre-motivation, and pre-satisfaction levels between both cohorts.Results (See Table 3) of the analysis indicated that there were no significant differences between the treatment (Cohort A) and control groups (Cohort A) in terms of pre vocabulary tests (p = .690,Z = 20.399),pre motivation levels (p = .737,Z = 20.336), and pre satisfaction levels (p = .838,Z = 20.205) at the significance level p = .05.It is thus evidenced that there are no significant differences in the range of vocabulary, motivation, and satisfaction levels at the beginning of the semester between the treatment and control groups, which established a baseline for further comparative analysis after the treatment.
The Mann-Whitney U test was conducted to determine whether there were significant differences in postvocabulary tests, post-motivation, and post-satisfaction levels between both cohorts at the significance level p = .05. Results (see Table 3) of the analysis indicated that there were significant differences between the treatment (Cohort A) and control groups (Cohort A) in terms of post-vocabulary tests (p = .003,Z = 22.946), postmotivation levels (p = .004,Z = 22.918), and postsatisfaction levels (p = .012,Z = 22.500) at the significance level p = .05.It is thus evidenced that there are significant differences in the range of vocabulary, motivation, and satisfaction levels at the end of the semester between the treatment and control groups.Therefore, we rejected the null hypotheses at the significance level p = .05that: (1) Learning outcomes in gamified English vocabulary learning are not significantly better than in non-gamified English vocabulary learning; (2) The motivation in gamified English vocabulary learning is not significantly stronger than in non-gamified English vocabulary learning; and (3) The satisfaction in gamified English vocabulary learning is not significantly higher than in non-gamified English vocabulary learning.

Results of the Semi-Structured Interview
Results of the semi-structured interview are generally in line with previous studies on the vocabulary tests, measurements of motivation (Hong et al., 2022;Qiao et al., 2022), and satisfaction levels.The majority (.80%) of interviewees believed that they could gain significantly better English vocabulary learning outcomes through Kingsoft Powerword than through non-gamified English vocabulary learning method.A larger proportion of interviewees (55%) believed learning English vocabulary through Kingsoft Powerword was more motivating than through non-gamified English vocabulary learning method.Most of them (.90%) prefer Kingsoft Powerword to non-gamified English vocabulary learning method in English vocabulary learning because they believed the former is much more convenient and thus satisfactory than the latter.Consequently, the results of the interview also rejected the three null hypotheses.

Discussion
This part will explore rationales for the research results.
It will be discussed based on the sequence of research hypotheses raised in this study.Learners with gamification could outperform their counterparts without gamification in terms of learning outcomes, motivation, and satisfaction.Generally, the results revealed align with the results of previous research (e.g., Connolly et al., 2012;Dib & Adamo-Villani, 2014;Riemer & Schrader, 2015).

Rationales for Different Learning Outcomes
English vocabulary learning is a long process of accumulation of knowledge.English vocabulary acquisition is a fundamental part of English language learning.Merely knowing the conception of a word does not mean mastery of it.Mastery of a new word does not mean merely knowing its meaning.Rather, the real mastery of a word indicates that the learner is able to use it in daily communication, speaking, and writing and to correctly understand it when listening and reading.Frequent access to target words is essential for mastery of words.The gamified Kingsoft Powerword, via storytelling, vivid sounds, animated pictures, interesting games, and native speakers' recordings, tends to attract students to vocabulary contacts and learning, which undoubtedly increases the learning frequency and prolongs the retention of words.By contrast, under non-gamified English vocabulary learning model, learners have to carry heavy dictionaries or paper materials and look for the words when they would like to decide the meaning of words.This has possibly decreased the frequency of and shortened the contact period of English vocabulary.Learning outcomes assisted with gamification are thus reasonably and significantly better than non-gamified English vocabulary learning approach.In addition, through vocabulary games, students could have the opportunity of contacting words that they are familiar with or unfamiliar with, which could ultimately facilitate the processing of words in their brains.It is, therefore, reasonable to conclude that learning outcomes in gamified English vocabulary

Rationales for Different Motivation Levels
Motivation often acts as a stimulus that can evoke human actions, enthusiasm, voluntarism, and goals.The word ''motivation'' originates from the word ''motive'' which is referred to as a sort of need that motivates people to act.The needs could be cultivated during the interactions with people, culture, lifestyle, society, and language acquisition.Motivation could play an important role in the cultivation process of needs.Needs could also exert a great influence on motivation.Positive motivation could facilitate the process of satisfying needs.In case that students hold positive motivation, they will engage in English vocabulary learning voluntarily, which will be helpful to enlargement of the range of English vocabulary.On the contrary, if students negatively assess the situation, they will be poorly motivated to engage in English vocabulary learning, which will lead to poor performance in learning outcomes and lower scores in vocabulary tests.
The gamified Kingsoft Powerword provides students with opportunities of learning English vocabulary with convenience, interest, fun, and enjoyment, which ultimately improves the learning outcomes.Non-gamified English vocabulary learning, however, requires students to carry heavy dictionaries and printed books.This led to less interest, lower desire, and inconvenience to learn English vocabulary, which unquestionably causes lower scores in the vocabulary tests.This in turn gives rise to the dampened motivation of English vocabulary learning.Consequently, it is normal to conclude that the motivation in gamified English vocabulary learning is significantly stronger than in non-gamified English vocabulary learning.
Motivation can be divided into both intrinsic and extrinsic motivations (Wouters et al., 2013).The intrinsic motivation refers to the self-desire to explore innovative things, to meet new challenges, to analyze learning competence, and to acquire new knowledge.It is driven by satisfaction, needs, desire, or enjoyment, which is hidden in an individual entity instead of external factors.The extrinsic motivation, however, is subject to external factors such as learning tools, materials, pedagogy, and learning settings.Gamification can firstly positively influence extrinsic motivation by reasonable teaching designs and flexible learning models, and secondly, enhance intrinsic motivation through enhancing learners' satisfaction.

Rationales for Different Satisfaction Levels
Satisfaction was evidenced positively correlated with interaction, self-efficacy, and self-regulation.Interaction, self-efficacy (Chang et al., 2022), and self-regulation, as important indicators of satisfaction, proved mutually and significantly correlated (Yu, 2015).The gamified vocabulary learning tool could improve three factors.With Kingsoft Powerword, students could interact with others by playing the contest game with other learners.They could compete with each other by taking part in the vocabulary game, from which rankings of game scores will be presented as game results.Ranking of the range of vocabulary can also render interactions with learners.Rankings could facilitate players' engagement in the gameplay process.Strong engagement could certainly improve learning outcomes, which would enhance students' satisfaction with gamified English vocabulary acquisition.
With gamification, players can improve their selfefficacy by actively joining the game-like learning activities.The games avoid the intense competition and the psychological nervousness by integrating the elements of enjoyment and entertainment.This relaxing situation can release the burden of vocabulary acquisition on learners.The self-efficacy can then be subconsciously increased and augmented with the progress of game-like learning and playing.With enhanced self-efficacy, students can naturally obtain relatively satisfactory learning outcomes and academic achievements, in turn improving self-efficacy.In this way, a benign cycle is formed, which is beneficial to the improvements in satisfaction.
During the gameplay process, players' self-regulation can also be enhanced.Immersed in the gameplay, very few distractions can disturb students' learning.They tend to possess strong self-regulation when playing games, especially when they are competing with other peers.In non-gamified English vocabulary learning, they tend to complain about the boring and dull vocabulary recitation and feel easily distracted.Their self-regulation will thus be weak, followed by dissatisfaction with the learning experience.The game-like learning process is attractive due to its variety of programs such as word matching, word contest, rich pictures, and vivid recordings.
There are still many other factors that possibly exert a great influence on the satisfaction of English vocabulary acquisition, such as game design, the difficulty of vocabulary, learning environment, and instructional approach.Interaction, self-efficacy, and self-regulation have, however, been demonstrated reliable and valid factors that determine the level of satisfaction (Yu, 2015).With the improved interaction, self-efficacy, and self-regulation, students' satisfaction will be enhanced with English vocabulary learning process.It is, therefore, reasonable to find that the satisfaction in gamified English vocabulary learning is significantly stronger than in nongamified English vocabulary learning.

Challenges in Gamified English Vocabulary Learning
Despite benefits of gamified vocabulary learning, challenges such as handwriting sense and spelling difficulties may draw researchers' attention.Although spelling and handwriting are different steps, they are closely related (Martinez-Garcia et al., 2021).With Kingsoft Powerword, students do not need to spell an exact word since the system can automatically complete the whole word if a proper reminder is provided.In this way, students' spelling abilities may be reduced.Their handwriting skills may also be weakened since they do not need to handwrite any word in the gamification-assisted contexts.Researchers could make every effort to overcome these obvious challenges facing gamified English vocabulary learning.

Conclusion
This part includes major findings, limitations of this study, and future research directions.

Major Findings
Two experiments, as well as a semi-structured interview, were administered to the randomly selected participants.The major findings of this study are that learning outcomes, levels of motivation, and satisfaction in gamified English vocabulary learning are significantly higher than in non-gamified English vocabulary learning.

Limitations
Serious games are of many kinds.Gamification in this study is limited to Kingsoft Powerword, which may lead to random errors in the result.The disproportion of males and females may also be a negative factor influencing the reliability of results.

Future Research Directions
Future research could include various serious games to testify the effect of gamification on English vocabulary learning.Interdisciplinary cooperation (Yu et al., 2020) between linguistics, statistics, education, and computer technology could also be implemented to study the effect of gamification.

Declaration of Conflicting Interests
The author declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding
The author disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work is supported by 2019 MOOC of Beijing Language and Culture University (MOOC201902) (Important) ''Introduction to Linguistics''; ''Introduction to Linguistics'' of online and offline mixed courses in Beijing Language and Culture University in 2020; Special fund of Beijing Co-construction Project-Research and reform of the ''Undergraduate Teaching Reform and Innovation Project'' of Beijing higher education in 2020-innovative ''multilingual + '' excellent talent training system (202010032003); The research project of Graduate Students of Beijing Language and Culture University ''Xi Jinping: The Governance of China'' (SJTS202108).
a Lilliefors significance correction.

Table 3 .
Results of a Mann-Whitney U Test.