Improving the Learning of Regular Verbs through TikTok among Primary School ESL Pupils ()
1. Introduction
Vocabulary mastery is a person’s exceptional ability to use words in a language, which they have developed based on their own interests, requirements, and motivation (Alqahtani, 2015). Therefore, using drilling methods to teach vocabulary would result in poor learning outcome and very low rate of improvement as the learner might regurgitate the vocabularies learnt within the lesson period and forget the meaning of the words afterwards. Pachina (2020) states that learning isn’t just about memorization; it’s also about understanding. Because memorization does not provide a deeper knowledge or meaning to the word or sentence, it is not recommended (Pachina, 2020). This proves that there is a need for teachers to shift the teaching methods used from time to time according to the era. Furthermore, the pupils who seemed like they remembered the verbs were hesitating to write or name the action given in the picture for sentence construction activities. This shows the pupils’ lack of interest in writing lessons in general. According to Carnegie Mellon University (2021), students lack interest in traditionally taught lessons because they have other priorities that compete for their time and attention.
It is most certain that a student-centred learning theory would act as a pillar in tackling this issue. The learning theory chosen was the Social Constructivist theory. In the language study of this theory, some individuals internalise social activities with increased language use, others lead to early behavioural changes and bridges, and subsequently it results in individual language development (Vygotsky, 1978). It is believed that with guided learning or activity engagement among peers in a group, learners’ language knowledge and abilities are built both internally and externally (Khadimally, 2021). There is a need for a suitable tool that bridges the gap between student-centered learning theory and the use of technology in teaching vocabulary. Vocabulary acquisition with technology has the potential to significantly improve the vocabulary development of school-aged second language learners (Yang, Kuo, Eslami, & Moody, 2021). There seems to be a variety of online platforms dedicated to aid the teaching and learning process such as Google Meet, Google Classroom, Google forms, Kahoot, Quizziz and many more. Despite the fact that these platforms are heavily used by teachers to give classes amid the ongoing Covid-19 pandemic, diverse online platforms capture students’ interest like a magnet. These platforms are known as social media apps such as Facebook, YouTube, Instagram, Twitter, TikTok and so on.
Social networks have increasingly risen in popularity, not only as a hot academic issue, but also as a core and pervasive means of digital and virtual communication for billions of people all over the world (Varga, 2018). Lately, social networks have been useful for sharing education related contents as well. This is proven when there are teachers creating accounts and sharing useful educational materials and going on live to teach or run programmes and short courses to attract an audience (Aguilar, Rosenberg, Greenhalgh, Fütterer, Lishinski, & Fischer, 2021). The audience in this context are the learners who seem to spend more time on social networks compared to platforms created solely for educational purposes. According to Khlaif and Salha (2021), TikTok, a popular social media app, has the potential to be a useful educational tool since it allows for the delivery of discrete learning units in a short amount of time (less than 60 seconds). Some creative teachers have created TikTok-based projects that are shared within private classroom groups, thanks to TikTok’s videography features. Using TikTok to create and deliver creative learning content can help pedagogical approaches based on nano-learning principles, making it easier to create high-quality e-learning content (Khlaif & Salha, 2021). Students could work individually or together to create content as they are very much creative and interested when it comes to TikTok. It is also obvious that most of the young learners tend to be Kinesthetic learners. However, there seems to be a research gap in the field of utilising TikTok for educational purposes. Therefore, the researcher saw this as an opportunity to increase the novelty of this research by using TikTok in writing lessons as an intervention that could be able to improve Year 5 pupils’ vocabulary in regular verbs.
2. Literature Review
2.1. The Importance of Vocabulary Knowledge in ESL
One of the most crucial components of studying a language is learning its vocabulary. According to Fisher and Frey, vocabulary is not a stand-alone talent; it lies at the heart of a language’s literacy. A language learner who does not have a large enough vocabulary will struggle in all aspects of the language. Word mastery students have a solid knowledge of the meanings, spoken and written forms, grammatical behaviour, word origin, collocations, word register (spoken and written), connotation or associations, and word frequency. Second language learners must have a strong vocabulary base to be competent or effective users of English in any educational setting. Furthermore, Alqahtani (2015) suggested that acquiring a sufficient vocabulary is critical for successful second language use since a language learner will be unable to apply the structures and functions we have acquired for meaningful communication if they do not have a wide range of vocabulary. According to several studies such as Nation (2001) and Alqahtani (2015), second language readers place a high value on vocabulary knowledge, and a lack of that information is the most significant barrier to overcome.
As a result, regardless of how well learners understand grammar and pronunciation, they will be unable to communicate effectively until they have a significant vocabulary. Moreover, vocabulary knowledge, as well as understanding of written and spoken information, are considered crucial tools for improving any language competence. Therefore, the more vocabulary learners are exposed to, the more confident they are in their ability to recognise and interpret novel words from context.
2.2. Social Constructivist Theory in Vocabulary Teaching and Learning
There is a need for a suitable theory that teachers could adapt into the teaching and learning of vocabulary. In this context a theory that is most suitable is Vygotsky’s Social Constructivist theory. According to the Social Constructivist theory on language study, individuals internalise social activities with increased language use, others contribute to early behavioural transformations and bridges, and subsequently results in individual language development (Vygotsky, 1978). His theory revolves around the concept of the zone of proximal development (ZPD). The ZPD is the difference between what a learner can do with and without assistance (Vygotsky, 1978). ZPD emphasised student-centred learning, with guided practice as a means of achieving learning objectives. Internally and externally, learners’ language knowledge and abilities are built through directed learning by teachers or activity engagement with peers in a group facilitated by their teacher. This student-centred theory is chosen for this research because according to Fiallos, Fiallos and Figueroa (2021), through active learning and group engagement, student-centred e-learning can engage students in a dynamic learning process.
Therefore, it is a teacher’s responsibility to bring this student-centred approach to application in the face-to-face or online setting. English, like any other language, requires all four skills such as Listening, Speaking, Reading and Writing. According to Ogle and Correa-Kovtun (2010), there is insufficient evidence to guide teachers in encouraging English language learners (ELLs) to improve their reading abilities on informational texts and learn new academic vocabulary that are important to be studied. However, students often learn informal texts through the social media platforms that they are very much interested in nowadays.
According to Mukoroli (2011), when the vocabulary list is chosen by someone other than the learner, vocabulary acquisition may be difficult, because the student-centered method emphasises the learner’s choice of preferred language. Personal vocabulary journals, according to Johnson (2016), are useful for learners to enter their chosen new vocabulary items. In the context of this study, teachers can encourage students to create their digitised vocabulary journals through social media apps such as Facebook, YouTube, TikTok and many more. Students are able to save it anywhere they like and share easily to their friends by tagging them or sending the soft copy of the videos or just easily find contents using hashtags such as #learnontiktok (Fiallos, Fiallos, & Figueroa, 2021). Hence, the teacher allows the students to choose what they are going to learn and increase their intrinsic motivation at the same time.
2.3. Students’ Acceptance toward Technology in ESL
The Technology Acceptance Model (TAM) is a model related to information technology that has been investigated in older populations to explain users’ acceptance and usage of new technologies, especially at first in the workplace (Davis, Bagozzi, & Warshaw, 1989). The TAM has been utilised as a grounding framework in a number of technology-related research, either in its original form or as a modified version (Davis et al., 1989) or in the extended model (Venkatesh & Davis, 2000). TAM is one of the most often used models of technology adoption, with two major elements influencing a person’s inclination to use new technology: perceived ease of use and perceived utility.
The TAM model has undergone extensive replication, improvement, and expansion since its first publication. According to Alfadda and Mahdi (2021) the TAM has been shown to be reliable and efficient in predicting technological uptake and adoption. The TAM explains that individuals’ performance of a specified behavior is determined by their behavioral intention to perform a certain task (Alfadda & Mahdi, 2021). In this study, TAM has been adapted into constructing the interview questions to act as a guide in understanding the students’ acceptance and perception towards using technology such as TikTok in the teaching and learning of vocabulary.
Firstly, behavioural intention to use would find out on how the students participated when TikTok was used and are they motivated to learn vocabulary because of that. Secondly, perceived usefulness would find out whether the students find TikTok as useful and help them improve in vocabulary mastery. As for perceived enjoyment and perceived ease of use, the researcher would know how fun or boring using TikTok was for them and the level of difficulty faced by the pupils to use it to learn vocabulary. According to Noh, Raju, Eri and Ishak (2021), TAM was useful to uncover significant understanding of students’ acceptance of online and distant learning in using digital tools for a better decision-making and students’ support assistance in their recent study. As a result, applying the TAM makes obtaining students’ approval of utilising technology in an ESL classroom, particularly in vocabulary mastering, simple and valid.
2.4. The Use of TikTok in Teaching Vocabulary
According to Cheah (2019) TikTok is the 5th most widely used social media among Malaysians. Furthermore, TikTok has been celebrated as the teenagers most widely used social media app after Instagram and Facebook. Students generate content either independently or collaboratively as they are very much creative and interested when it comes to TikTok. There are several past studies that have been conducted regarding the use of TikTok in teaching English language.
Risma Galuh (2021) conducted a study about Student’s Perception toward The Use of Tik Tok in Learning English Vocabulary published in the Khazanah: Jurnal Mahasiswa. The research used surveys as research design by applying online questionnaires as instruments. Looking at the results of the survey, it could be implied that short videos on TikTok that contain English material contents help the participants to expand their English vocabularies. Students have given favourable comments on using TikTok as a language learning medium since the English content videos were simple to grasp and retain various vocabularies they found on those films, such as vocabulary for verbs, nouns, and other topics. Risma Galuh (2021) concluded that using TikTok as the media for learning language can be considered nowadays. Students expressed the positive impact of English material contents which increased their vocabulary by watching those videos.
Noor Syazana, Kamini, Wan Izzati and Melor (2019) conducted a study on TikTokActiV in Enhancing ESL pupils’Writing skill focusing on Action Verbs which was published in the International Journal of Innovative and Applied Research. It was conducted among 60 primary school pupils from a rural school, a sub-urban and an urban school in the southern part of Malaysia. The progress of the students’ writing skills was assessed using a 20-question pre- and post-test. The effectiveness of employing “TikTokActiV” was investigated using an action research approach. According to the results of the pre- and post-tests, using TikTokActiV as a teaching tool in English language classes will result in considerable gains in ESL writing skills.
Diana, Wendy, Claudia and Melor (2020) conducted a study about Enhancing Form 4 Pupils’Speaking Skills via TikTok. They executed a programme called #TikTokTell for a duration of 4 weeks and provided the module as a guide for facilitators. The researchers collected the data through conducting a pre-test in week 1 and a post-test in week 4. After that, the facilitators of the programme carried out a classroom assessment and analysed the improvements of the students. Based on the researchers’ findings, it was proven that participants’ ability to speak was enhanced after conducting the “Let us #TikTokTell” programme. The participants also began to use more adjectives by the end of the fourth week. Furthermore, in their video production, the students were able to provide more elaboration on the topics given to them. Therefore, based on the past studies, social media, especially TikTok seems to be very effective for the primary and secondary ESL classroom.
Therefore, with proven studies it is obvious that TikTok aided students in learning “differently” and is an important forum for teaching academic material and promoting social/emotional well-being (Solomon, 2021). TikTok offered a novel approach to education, combining technology, kinaesthetic movement, and social collaboration/collective learning. To summarize, the usage of the TikTok application is extremely influential since it is beneficial and offers advantages such as making studying easier and more enjoyable, allowing users to watch entertaining videos, conduct company, and quickly learn about current events around the world, as asserted by Pratiwi, Ufairah and Sopiah (2021).
3. Methodology
3.1. Research Design
This research used a mixed method which is a combination of quantitative and qualitative methods since the study aimed to describe and understand the students’ achievement as well as their perception in the process of vocabulary teaching and learning through TikTok social media application. Since the researcher is not bound by the tenets of a single technique of research, Wisdom and Creswell (2013) agree that using a mixed method of research allows him or her to address a larger and more comprehensive variety of research issues. Furthermore, researchers have the potential to exploit the strengths of one research approach to compensate for or overcome the flaws of another (UKEssays, 2018).
3.2. Research Samples
As this research aims to use primary data, the researcher used convenience sampling. Convenience sampling is a type of sampling where the first available primary data source will be used for the research where you include people who are easy to reach without additional requirements (Etikan, 2016). The sampling is done by choosing the students from a Year 5 class taught by the researcher that was mentioned in the problem statement section. The class chosen for this study are of mixed proficiency which includes high proficiency, intermediate proficiency and low proficiency students. A total of 45 participants took part in this study where their identities were kept anonymous. The participants are from a national school in Klang that is located in a sub-urban area. They comprise of 20 boys and 25 girls who are at the age of 11 years old and they are all Malay race students.
3.3. Research Instruments
There were two instruments used to collect data from the participants of this research. The instrument that collected the quantitative data would be tests. Pre-test was conducted before using TikTok and Post-test was conducted after using TikTok for the teaching and learning process of vocabulary. Both the tests comprise of two sections, namely Section A and Section B. Section A includes a fill in the blanks task comprising pictures and sentences with missing verbs. The verbs will then be provided on the whiteboard in a jumbled up manner. As for this section, the pupils’ ability to correctly choose the correct verb to fill in the blanks would be assessed. Section B includes 8 sentence construction task. As for this section, pictures would be provided with a word clue (object). The pupils should guess the verb according to the picture and use the word clue to construct an SVA sentence. As for this section, the students’ ability to identify the verb and construct sentences would be assessed. All 45 participants took the test to contribute to the quantitative data of this research.
The other instrument that collected the qualitative data would be the semi-structured interview. A total of 10 students were picked from the participants to be interviewed. The semi-structured interview comprises of 6 pre-planned questions and a few open-ended questions to get additional information after listening to the participants’ answer. The pre-planned questions were adapted from the Technology Acceptance Model (TAM). Technology Acceptance Model has been one of the most influential models of technology acceptance, with two primary factors influencing an individual’s intention to use new technology: perceived ease of use and perceived usefulness (Charness & Boot, 2016). Since its original publication, the TAM model has undergone substantial replication, refinement, and extension. Hence, the interview questions were divided into 4 sections with 2 questions and an open-ended question wherever appropriate according to the participant. The four sections are namely perceived usefulness, perceived enjoyment, perceived ease of use and finally behavioural intention to use.
Therefore, a pilot test will not be conducted prior to this study. This is because, the researcher is confident that by using the quantitative data and qualitative data gained from the two instruments to analyse the effectiveness and the perception of the participants would increase the reliability of this study. Moreover, by adapting TAM in designing the semi-structured interview, the validity of the response increases, as this model has been adapted and used in many past researches to measure the human behaviour towards technology.
3.4. Data Collection Procedure
The research was conducted in a Year 5 class of a national primary school which is located in Klang. An information sheet attached with a consent form was distributed to all 45 participants to be brought back home to be discussed with their parents before giving consent. This was given one week before the research was conducted in the class. Harish (2017) stresses that parental consent is required when the child is incapable of understanding the effects of taking part in a research study. As this research includes participants who are below 18, the researcher took this necessary precaution. Although the children are permitted to complete their tasks, permission is required to notify their parents or legal guardians as a precaution and assurance to the school. An interview protocol was also strictly followed by the researcher to avoid any issues from happening.
The selected participants attended the class conducted by the researcher with 100% attendance. With this positive start of full attendance, the input was delivered and the students participated in watching and reacting to the TikTok videos made by the researcher. Then, the researcher gives a homework on creating their very own TikTok videos explaining a regular verb which will be a duet beside the researcher’s initial TikTok videos. This happens obviously with parental supervision for safety purposes. The instructions of the researcher were followed by the participants throughout this whole process. It is crucial to follow the researcher’s instructions an adhere to the rules because it is an extended 2 days’ process.
After that, the same test with section A and section B was conducted on the second day after the pupils were done creating TikTok videos on verbs. They were briefed before the test by the researcher. After completing the test, the results were given to them on the same day. Then, 10 participants were randomly picked from the sample for the interview session. The total duration to collect data was a whole of two days. However, the students continued to explore on creating TikTok duets with the researcher’s regular verb videos.
3.5. Data Analysis Method
The two instruments used to evaluate the research objectives and to answer the research questions aided in improving the study’s reliability and validity. Therefore, triangulation of data had occurred. Triangulation is a strategy used to boost the reliability and validity of study findings, according to Noble and Heale (2019). Validity is concerned with the extent to which a research correctly represents or evaluates the notion or concepts being explored; credibility relates to trustworthiness and how credible a study is (Noble & Heale, 2019).
Firstly, data collected from the tests which were the scores were then tabulated and analysed using percentages. The tabulation of test results is divided into three sections comprising section A scores, section B scores and the total score in percentage (%). The scores are analysed according to the percentage achieved across low to high proficiency students. Moreover, the data is also analysed using mean score (μ) to discuss the average achievement of the whole Year 5 class chosen. These scores are used to determine how successful the TikTok application is for learning English, especially vocabulary when used effectively.
Secondly, data collected from the semi-structured interview which were the students’ individual answers were then analysed using thematic analysis method. The responses were turned into an interview transcription to easily analyse the response. The similarity in answers given and repeated words were used to form emerging themes. Moreover, the emerging themes were arranged in a table format according to the four main sections namely, behavioural intention to use, perceived usefulness, perceived enjoyment and finally perceived ease of use. The frequency of the positive and negative emerging themes was analysed to represent the interest of the students in using TikTok for educational purposes, whether the platform is assisting them in learning English vocabulary in a more efficient manner, their feelings while using an alternative such as TikTok for learning, and if it was easy to use it for creating vocabulary videos. These representations are seen in the table based on the accuracy of the interviewees’ statements. The conclusion from the table will be analysed and discussed in the next chapter.
4. Findings and Discussion
4.1. Pre-Test and Post-Test Result
To begin, the pre-test and the post-test consist of the same test items to have a clear picture on the pupils’ improvement. As presented in Table 1, the difference score (n%) indicates the level of improvement made by the pupils in their post-test after receiving a lesson by the researcher through TikTok. The mean score (μ%) is calculated to indicate the average score achieved by the pupils and the mode score (%) is to indicate the most frequently received score from the 45 pupils.
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Table 1. Pre-test and Post-test results.
As shown in Table 1, all the pupils have improved in their post-test by showing an increase in marks. Although some pupils’ difference in score is lower than 32% such as pupil 42, 43, 44, and 45, a majority of the pupils gained a difference in score that is more than 40%. An average score of 32.5% obtained by the pupils in their pre-test have evidently increased up to 80.7% in their post-test. This tremendous increase shows the effective rate of using TikTok to teach regular verbs and sentence construction. Hence, it can be inferred that the TikTok application can be used to assist pupils and teachers in teaching and learning practices in the twenty-first century, as asserted by Pratiwi, Ufairah and Sopiah (2021).
Moreover, the most frequent score achieved by pupils in their pre-test was 42% with a total of 9 pupils achieving this score and in their post-test was 75% with a total of 9 pupils achieving this score. Although these 9 pupils are not exactly the same ones, it is highly commendable that even the lowest score which was 0% has increased above 50%, precisely 58%. Furthermore, the highest score which was 69% has hiked up to 98% which is almost a perfect score. According to Nabilah, Lazuwardiyyah, Syaifuddin and Abdi (2021), using video to allow video help is a more successful approach in terms of teachers’ ability to notice and interpret classroom experiences. Meaning to say that the TikTok videos will assist students in independently learning verbs and sentence construction.
4.2. Interview Results
As for interview results, the items were individually analysed using thematic analysis. The frequency of the positive and negative emerging themes was analysed using the frequency (n) of the 10 pupils who responded with similar answers according to the themes.
Table 2 shows the interview results collected based on the perceived ease of use. The highest frequency of the positive response was recorded by item No.1, where 9 pupils were claiming that “it was easy to search for English lessons in TikTok”. Comparatively the highest frequency of the negative response was recorded by item No. 3, claiming that they “have not tried making their own videos in TikTok”. Overall, 7 out of 10 pupils find TikTok as an easy app to use. Likely, Yunus, Zakaria and Suliman (2019) asserted that social networking applications are simple and effective platforms for bridging connectivity gaps by fostering social support and assistance and generating a desire for learning.
As shown in Table 3, all four items were determined to analyse the perceived usefulness of TikTok in teaching verbs and sentence construction. It is obvious in the table that all four items received positive responses and none of the interviewees gave a negative response. In detail, all the 10 pupils understood the lesson delivery through TikTok, agreed that the content of the video was clear enough, and agreed that they improved in their post-test after watching TikTok videos. Although the final open-ended question recorded various types of responses, they were all positive responses describing how TikTok helped them construct sentences using verbs. Evidently, half of the interviewees claimed that just watching the videos have helped them in constructing sentences using verbs. Therefore, it can be summarised that TikTok is 100% usefull and effective based on the 10 pupils who were interviewed.
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Table 2. Interview results based on Perceived Ease of Use.
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Table 3. Interview results based on Perceived Usefulness.
Table 4 represents the interview results collected based on perceived enjoyment. As seen on Table 4, item 1, 2 and 4 received positive responses from all the interviewees. This shows that the pupils felt good/happy after the lesson using TikTok, had fun while watching TikTok videos and enjoyed the whole lesson compared to previous lessons. Solomon (2021) demonstrated that TikTok aided students in learning “differently” and is an important forum for teaching academic material and promoting social/emotional well-being. This point was also proven when the pupils responded that they enjoyed the lesson because 4 of them liked the TikTok videos and 6 of them found it interesting compared to previous lessons. Unfortunately, 3 of the pupils could not have fun creating their own TikTok videos because it was difficult for them. As a whole, the majority enjoyed the lesson thanks to TikTok.
Table 5 depicts the pupils behavioural intention to use TikTok in learning English Language as a whole. In this section of the interview, all the pupils responded positively to item No. 1, 2 and 3. Precisely 7 of the pupils were keen on downloading the TikTok app and 3 of them claims that they already have it. Fortunately, all 10 pupils intend to watch educational contents posted in TikTok. Moreover, all of them mentioned that they would try making their own TikTok videos related to English Language learning in future. This is because, 6 of them like TikTok, 3 of them want to explore and 1 pupil wants to teach friends and siblings. Relatively, as Yunus, Nordin, Salehi, Embi and Salehi (2018) mentioned, the integration of social media into English learning encouraged students to be self-sufficient and accountable for their learning by intelligently searching for educational materials online. However, as shown in Table 5, 3 pupils are still not ready to create their own educational content on TikTok as they need more practice. Students in today’s generation are always on the lookout for new information, and it is exhaustively fair to say that they enjoy a change of pace from their usual classroom routine to something more technology-based (Hashim, Rafiq, & Yunus, 2019). As a result, the TikTok application’s acceptance rate as a great platform for learning pronunciation is unquestionably high, owing to the current generation’s interest in incorporating technology into their education.
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Table 4. Interview results based on Perceived Enjoyment.
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Table 5. Interview results based on Behavioural Intention to Use.
5. Conclusion
Good vocabulary knowledge helps in developing writing skills when it comes to sentence construction. This particular skill can be very challenging for primary second language learners. As evidently proven through this study, all the participants of this study achieved different levels of improvements with the help of TikTok as an intervention of the lesson delivered. It is also very much clear in this study that the pupils really enjoyed the lesson when TikTok was involved, found it effective and very easy to use in making their own verb videos, and most of them were keen in creating educational contents in future. However, some of the pupils faced difficulties in creating their own TikTok videos and it was not fun for them. This is because TikTok is an app with many features that keep updating. It depends on the individual’s interest and rate of learning to be able to grasp the process of making videos. The given time for this research was not enough for the respective pupils to practice and get used to making TikTok videos. Once, they practice and get the hang of it, there will be endless possibilities in making educational videos. Not to mention that there are debatable practicality issues as well such as parents’ fear of their children’s exposure towards social media as they might come across mature contents followed by privacy policy issues such as pupils accidentally posting a stranger’s personal information on their videos. These issues can be avoided by simply setting the privacy control options in TikTok to enable the app to filter the contents. Moreover, the privacy policy issue can be avoided if the pupils use their gadgets under adult supervision.
Furthermore, this study might be useful for future researchers to further dive into the endless possibilities of educational practices through TikTok worldwide. For example, this study may also be used to develop online speaking activities and authentic networking among students, educators, and parents using the TikTok application. The usage of technology and social media in the learning classroom breaks down boundaries and transforms them into a productive learning environment across the globe. It is suggested for future research that TikTok be utilized for several sorts of language abilities other than speaking abilities, such as listening, reading, or writing abilities not only for second language learners but also for foreign language learner and natives themselves for different language such as French, Spanish, German, etc. Educators might utilize the Tiktok app to encourage and improve students’ pronunciation in speaking for communicative and educational purposes. This study is important especially during this digitised era and online learning phase due to Covid-19 pandemic. Therefore, this study concludes that TikTok is indeed an effective teaching tool, especially when it comes to teaching language.
Acknowledgements
The authors would like to acknowledge Universiti Kebangsaan Malaysia for the support given under the research grant no. GG-2022-007.