The Acquisition of Japanese Case Particles by Indonesian Learners of Japanese:

This research is a continuation of previous research. In previous research, the author examined the effect of the theoretical explanation of the Japanese adnominal clause on the learners’ understanding. However, in this research, it was discovered that students’ knowledge of case particles in Japanese is a key determinant of understanding Japanese adnominal clauses. In this research, the author tries to examine the effect of students’ understanding of case particles in Japanese through the concept of Kou (argument) in verbs. In line with previous research, in this research, the author also tries to bridge the theoretical concepts of linguistics so that they can be applied to Japanese language learning in the classroom. In this research, the author took 20 second-year students as a sample and divided them into two groups. In the experimental group, the author used the Focus on Form (FoF) method to teach the concept of the verb “argument” so that students could determine the correct Japanese case particles. Meanwhile, in group control, they only do pattern practice exercises like a normal class. The test analysis results of the two groups after attending the experimental class did not show any significant differences. In future research, it is necessary to look at the long-term influence of applying linguistic theory in the classroom.


INTRODUCTION
This research is developed based on the results of the experiment conducted in Maarif (2021).Maarif (2021) attempted to help Indonesian Japanese learners understand adnominal modifier clauses by using the concept of uchi soto or 'inside/outside relations'.The results showed that the test was somewhat successful in determining the relationship between inside and outside.However, it was found that in sentences with internal relations, learners did not perform well on returning the head noun to the main clause.There were many errors in case particles and clauses.In other words, it is found that it is important to establish an understanding of case particles and clauses before helping students understand adnominal modifier clauses.Based on the e-ISSN 2528-5548 | p-ISSN 27764478 experimental results of Maarif (2021), this study attempted an experiment to help learners understand case particles.
( Case particles are considered to be items that learners are likely to make mistakes even when they become advanced learners, even though they have learned them from the beginner level.One reason for this is thought to be that one particle has multiple roles.The conditions for which particles to use in which situations are explained in class.However, it is thought that learners may get confused due to a large number of conditions and may make mistakes when producing them.Therefore, this research uses the linguistic concept of 項 "kou" (argument) to help learners understand case particles, and it is thought that they may be able to produce case particles more accurately.
When there is no premise, example sentence (2) a and b do not work as a sentence because we do not know who Taro hit in a, and who hit Hanako in b.The above example sentence (2) c is valid as a sentence because c has all the information needed to understand the sentence.As shown in example sentence (2) c, for the predicate verb "to hit" to be valid in a sentence, information on "who (actor)" and "to whom (object)" is essential.This essential information is called "argument".On the other hand, information such as 昨 日 "kinou" (yesterday) and 公園で "kouen de" (in the park) can be considered as a sentence even if it does not appear in the sentence as in the example sentence (1), so it is not considered to be The concept of "argument" is considered to be quite difficult for learners, so it probably won't be taught in class.However, in this experiment, when thinking about Japanese verbs, the class will have students refer to the meaning and grammar of Indonesian and think about the necessary "argument".

LITERATURE REVIEW Multiple Meanings of Case Particles
Many studies have been conducted on the acquisition of Japanese case particles.Among them, Oka (2007) analyzed the polysemous meanings of case particles from the perspective of cognitive linguistics and proposed a semantic network schema for the case particles ni, wo, de, and ga.It states that the prototype meaning of each case particle has been extended to various usages, as listed in Table 1.Although Oka's (2007) analysis from the perspective of cognitive linguistics is very interesting, it is considered to be extremely difficult for learners who are learning Japanese as a second language.Advanced learners who have studied or are interested in linguistics will be aware of the variety of different uses of case particles and will not be able to provide an explicit explanation of how they extend from the prototypical meaning of case particles.However, it is too difficult for elementary and intermediate level learners.e- ISSN 2528-5548 | p-ISSN 27764478 In this study, by introducing the concept of 項 kou "argument", which is less difficult, in the actual class, learners will be able to influence the production of case particles.

Focus on Form (FonF)
The concept of Focus on Form (FonF) was proposed by Long (1988).Fundamentally, FonF refers to the shift of the learner's limited attention to linguistic codes during comprehension or production recognition in meaning-centered second language acquisition settings ( Long & Robinson, 1998).
Besides FonF, there are also Focus on Meaning (FonM) and Focus on FormS (FonFS).Although the names are very similar, FonFS is like a traditional grammar or structure syllabus, where learners learn the grammar of a language little by little It is said that learners using this method had good language proficiency, but lacked language fluency.On the other hand, FonM is often used in learning methods such as immersion, which allows learners to acquire fluency at an early stage, but it is said that it takes time for learners to acquire the characteristics of the language (Koyanagi, 2004).
An important point in FonF is to consider the use of language in actual communication.In other words, the main premise is to develop both the character and fluency of the language.for that purpose, it becomes essential for learners to discover and analyze the relationship between language form and meaning.
In this study, we conducted an experimental class in which we had students think about the terms that each verb requires based on the meaning of Japanese verbs in Indonesian, and then generate case particles so that the terms express the appropriate relationship.In other words, this research tried to incorporate FonF's method into my classes by paying attention to the necessary language codes to convey the meaning of verbs correctly.

Subject of Experiment
The survey for this study was conducted in an experimental class on July 20, 2022.The survey was scheduled to target students with Japanese Language Proficiency Test N3, but the exam was not held due to the coronavirus pandemic.As a result, many students were unable to take the exam and were unable to master N3.Taking this into consideration, the subjects for the experiment were 20 second-year students majoring in Japanese at an Indonesian university.The 20 subjects were divided into two groups, an experimental group and a control group, each with 10 people.
Tests were administered before and after the experimental class.The test consists of two types of questions with a total of 35 points.For question 1 (10 questions x 2 points), the task is to look for misused case particles and correct them by marking the correct ones with an O and the incorrect ones with an X. Question 2 (15 questions x 1 point) is to include the correct case particle in the sentence.
The type and number of required items will be set similarly for the pre-class and post-class tests.However, in the follow-up class, taking into consideration the test results before and after the class, we asked a larger number of が "ga" に "ni" questions in question 1 (5 questions).Grouping was done based on the results of the pre-class test, adjusting subjects with high and low scores so that each group had the same average score.After dividing the students into groups according to Table 3 below, classes were given to each group.The experimental group was given an explicit explanation of the concept of "argument" by comparing it with Indonesian, while the control group was given only a lesson on traditional particle pattern practice.Classes for both groups were conducted online using Zoom Meeting.

Samsul Maarif,
The Acquisition of Japanese Case Particles by Indonesian Learners of Japanese: Focusing on the Concept of Kou "Argument" of Verb e-ISSN 2528-5548 | p-ISSN 27764478 Class Flow for Experimental Group 1.In the experimental group's class, the students first learned that sentences consist of a subject, an object, and a predicate, and we focused on verb-predicate sentences.2. After that, they looked at intransitive and transitive predicate sentences, identified the necessary elements for each to become a sentence, and introduced the concept of "argument".3. We introduced the types of essential argument and optional argument and confirmed the case particles used there.4. The role of case particles in expressing the relationship between nouns and predicates was explicitly explained and contrasted with the Indonesian concept. 5.In Indonesian, the concept of expressing the relationship between nouns and predicates is explicitly explained using word order and affixes.6. Use the meanings of the verbs, think about the necessary argument, and look at examples of 一 項動詞 "Ichi kou doushi" (unary verbs)・二項動 詞 "Ni kou doushi" (binary verbs)・三項動詞 "Sankou doushi" (ternary verbs).

Class Flow for Control Group
In the control group, we did not particularly explain concepts related to terms, and the class focused on traditional particle pattern exercises.Below is the exercise pattern.1. Pattern 1: Look at pictures and practice making correct sentences.2. Pattern 2: Practice filling in blank spaces with correct verbs.3. Pattern 3: Practice inserting the correct case particle into the blank part of the sentence.4. Patterns 1-3 were performed twice. 5. Pattern 4: Practice choosing intransitive and transitive verbs to form correct sentences (twochoice questions).
As mentioned above, the experimental group was given an explicit explanation of the concept of "argument" and a comparison with Indonesian, whereas the control group was taught only conventional particle pattern practice.After the lesson, both groups were given a post-class test.
For the post-class test, we tried to choose words that were similar in meaning to the words used in the practice.For example, using the word 壊す "kowasu" (destroy) during practice, and used the word 破壊する "hakai suru" (to destroy) during the post-class test.
The post-class test was conducted as homework to be submitted the next day after completing the online class.
A follow-up class was held three weeks later based on the pre-class and post-class test scores and comparison results.The follow-up class consisted of checking the answers to the post-class test, and the students were given test questions after the follow-up class and were told to submit them the next day.

RESULTS AND DISCUSSION
Table 4 shows the test results (out of 35 points) for 20 subjects."Pre" represents the pre-class test results, "Post" represents the post-class test results, and "Follow" represents the follow-up class test results.These results showed that the control group performed better on the post-class test than the experimental group.The average of the control group was found to be 32 points compared to the experimental group's average of 31 points.Interviews and tests were conducted in a follow-up class three weeks after the post-class test.As a result, the experimental and control groups obtained the same average score of 30 points.In addition, this study found that by introducing the concept of "argument", learners were able to understand and produce case particles better than in conventional pattern practice.In other words, we hypothesized that there would be a significant difference between the experimental group and the control group.The most commonly used statistical method to test hypotheses is P-value testing.
To prove that there is a difference between the experimental group and the control group, First, we hypothesize that there is no difference between the experimental group and the control group, and use the null hypothesis to prove that hypothesis wrong.By rejecting the hypothesis that there is no difference, we can prove that there is a difference.
If there is significance between the experimental group and the control group, the P value is <0.1.To calculate the P value, we entered the data in Microsoft Excel and used a data analysis tool called "t-test: Two-sample test assuming equal variance".The T-test examines whether there is a difference between the average values of the two data groups (Shimada & Noguchi, 2017).
A T-test was performed on the results of the post-class test and follow-up class test to determine the P value.As a result, the P values were found to be 0.54 and 0.95, as shown in Tables 5 and 6.Both P values are >0.1, meaning there is no significant difference between the experimental and control groups.
The test result data showed that there was no significant difference between the experimental group and the control group, so the hypothesis of this study could not be proven.

Pre-Class Test Result Analysis
Tables 7 and 8 show the number of people who gave incorrect answers to questions in pre-class tests' question 1 and question 2 (frequency of incorrect answers).
In pre-class test question 1 (questions that look for misuse), the ones with the highest frequency of incorrect answers were number 3 in the experimental group and number 9 in the control group.Question number 3 is 友達が朝の授業を出ませんでした "Tomodachi ga asa no jugyou wo demasen deshita" (My friend didn't come to class in the morning).The case particle in question 3 is incorrect, so the correct answer is × and を→に "wo → ni".However, in the experimental group, four students answered 〇, and two students who answered × also corrected the wrong case particles, such as を→が "wo → ga" and を→で "wo → de".Question number 9 is 信号が壊 れて、警察を困りました "Shingou ga kowarete, keisatsu o komarimashita" (The traffic lights were broken and the police were in trouble).The case particle is incorrect, so the correct answer is × and を →が "wo → ga".However, in the control group, there was one student who answered 〇, and three students who answered × also used the wrong case particles as を→に "wo → ni" and corrected the wrong case particle (wo → to) instead of を→が "wo → ga".
In pre-class test question 2 (questions that include case particles), the frequency of incorrect answers increased, and the highest frequency of incorrect answers was in questions 10 and 12.
The test subject's answer was の "no", を "wo", と "to", and を "wo" because there is a 友 達 "tomodachi" (friend) as "person".This answer is not wrong in the context, but in this study, it was counted as an incorrect answer because it was set to represent the destination.This question is a shortcoming of this study, and it would have been better to use words that expressed the destination, such as 隣のビル "Tonari no biru" (building next door) rather than 友達 "tomodachi" (friend).
In the pre-class test, students have not yet taken the experimental class, so as mentioned above, students may interpret the question sentences in various ways.

Post-Class Test Result Analysis
Tables 9 and 10 show the number of people who gave incorrect answers to questions in question 1 and question 2 after class (frequency of incorrect answers), respectively.In post-class test question 1 (questions that look for misuse), questions 1, 2, and 7 were answered incorrectly most frequently by 7, 9, and 5 students.
The first question is 赤ちゃんがお母さんの手 に握っている "Akachan ga okaasan no te ni nigitte iru" (The baby is holding the mother's hand).The case particle is incorrect, so the correct answer is × and the correct particle is に→を "ni → wo".For this question, the experimental group (5 students) answered incorrectly more frequently than the control group (2 students).As a result of follow-up interviews, it was found that because the subjects learned in class that the case particle "ni" expresses contact, they overgeneralized that the verb 握る "Nigiru" (hold) also expresses contact.Care must be taken when handling the explanation in linguistic theory that に "ni" case represents "contact" in educational settings, and a more specific explanation is considered necessary.
Question number 2 is 弟が国の大事なプロジ ェクトを参加しました "Otouto ga kuni no daijina purojekuto wo sankashimashita" (My younger brother took part in an important national project).The case particle is incorrect, so the correct answer is ×, and the correct particle is を→に "wo → ni".However, 9 students answered 〇, with 5 students in the experimental group and 4 students in the control group.Even though the experimental group learned verbs with the same meaning, such as 加える"kuwaeru" (add), 加わる "kuwawaru" (join), and 参 加 す る "sankasuru" (take part/participate), the reason that it is still incorrect may be because each verb is recognized as a different thing.
Question number 7 is 桃太郎が鬼ヶ島で鬼を 戦う "Momotarou ga onigashima de oni o tatakau" (Momotaro fights demons on Onigashima).Since the case particle is incorrect, the correct answer is ×, which means を→と "wo → to".This question uses a verb with the same meaning as question number 8 喧嘩する "kenkasuru" (fight) in the preclass test, and when comparing the two, it was found that the frequency of incorrect answers increased.In addition, subject number 6 in the experimental group answered correctly in the preclass test but answered incorrectly in the post-class test.In the control group, it was confirmed that subjects 5, 7, and 9 were no longer able to do it after class.As confirmed in the follow-up interview, number 6 in the experimental group incorrectly interpreted the verb 戦う"tatakau" (to fight) as 攻 撃する "kougeki suru" (to attack) in Indonesian.Since it is a transitive verb, they thought the required term was を "wo" instead of と "to".In e-ISSN 2528-5548 | p-ISSN 27764478 addition, subjects 5, 7, and 9 in the control group also said that を "wo" was correct because 戦う "tatakau" (to fight) is a transitive verb.In both groups, the answer was incorrect due to the generalization of transitive verbs.が "ga" 0 0 0 4 入室する "Nyuushitsu" (enter the room) が "ga" 0 3 3 Question 1 subtotal 38 27 59  Overall, the post-class test question 2 (questions involving case particles) was better than the preclass test.Here we see the highest frequency of incorrect answers for numbers 12 and 7, with 7 and 6 students respectively.
Question number 12 is 太郎くん( )花子 ちゃん( )ほめました "Taro kun ( ) Hanakochan ( ) homemashita" (Taro-kun praised Hanakochan), and the correct answer are が "ga" and を "wo".For this question, the experimental group (5 students) answered incorrectly more frequently than the control group (2 students).Most of the incorrect answers were が "ga" and に "ni", and as a result of confirming this in the follow-up interview, it was found that students chose 二格 "ni kaku" (ni case) because they thought "Hanako chan" was the arrival point of ほめる"Homeru" (Praise).In other words, it can be said that in this question as well, the subjects in the experimental group overgeneralized the meaning of 到 着 点 "touchakuten" (point of arrival) in 二格 "ni kaku" (ni case) that they had learned in class.
Question number 7 is 弟( )妹( ) いじめる "Otouto ( ) imouto ( ) ijimeru" (brother teases sister), and the correct answer are が "ga" and を "wo".The frequency of incorrect answers for questions was higher in the experimental group (4 students) than in the control group (2 students).Also, in this question, as with question number 12, the student's incorrect answer was が "ga" and に "ni", and it is thought that the student overgeneralized by thinking that the younger sister was the arrival point of "teasing".
Table 12 below is incorrect answers for postclass test question 2 number 7 and number 12.

Follow-Up Class Test Result Analysis
A follow-up class was conducted because the experimental group's results were not significantly different from the control group in the post-class test.In the follow-up class, the participants' answers to the post-class test were reviewed to confirm their understanding.After that, tests were conducted and the results are shown in Tables 13  and 14.
In question number 8, the case particle in お父 さんが留学を賛成してくれました "Otousan ga ryuugaku o sansei shite kuremashita" (My father agreed for me to study abroad) is incorrect, so the correct answer is ×, which means を→に "wo → ni".However, both the experimental group (6 students) and the control group (six students) answered yes.In this problem, the students likely focused on the transitive verb 賛成する"Sansei suru" (agree) and did not realize that 二格"ni kaku" (ni case) was a necessary conjunction.
In the Follow-up class' Question 1 numbers 5, 8, and 10, if the subjects in the experimental group understood the Indonesian meanings of 挑戦する "chousen suru" (challenge), 賛成する "Sanseisuru" (agree), and 離れる "Hanareru" (apart), they would be able to identify the necessary terms for each verb.Although we predicted that the subject would be able to find the term, it can be said that the subject was still unable to successfully find the necessary term from the meaning.This is induced by transitive verbs, and the binary verb が "ga"・に "ni" is a special verb and is thought to be difficult to learn.
In the follow-up class, test question 2 (questions involving case particles), question number 14 had the highest frequency of incorrect answers with 14 students.The item with the second highest frequency of incorrect answers was number 15 (5 students).
Table 15 below shows incorrect answers for follow up-class test question 1 number 5 and number 10.

Discussion
In the experimental class of this research, we tried to use the concept of "argument" of verbs to help people understand case particles.However, as evidenced by the statistical data, no meaningful difference could be confirmed between the experimental group that learned the concept of "argument" and the control group that did not.
The following are possible reasons why there was no meaningful difference between the experimental group and the control group.
This study had the disadvantage that the subjects were second-year students and the verbs used in the experimental class were too difficult.The subjects in the experimental group were able to understand the concept of "argument" well, but even when verbs with the same meaning were set in the test, the subjects were unfamiliar with the verbs, so they did not fully understand the meaning, which shows the shift of the learner's limited attention to linguistic codes during comprehension or production recognition ( Long & Robinson, 1998).Therefore, when considering the necessary terms of the verb, it is thought that the transitivity of the verb leads to the assumption that verbs that require が に"ga ni" and が を "ga wo".
In addition, in the experimental group class, we practiced grouping verbs in the same category, such as ヲ格 "wo kaku" (wo case), 二格 "ni kaku" (ni case), and ト格 "to kaku" (to case), into binary verbs.The purpose of this exercise is to acquire the ability to predict which category term is required when there are similar verbs.However, subjects did not make predictions based solely on the meaning of the verb, but based on context such as co-occurring nouns ( 目 的 語 "Mokuteki go" (objects)).For example, in the post-class test, for the question 赤ちゃんがお母さんの手に握って いる "Akachan ga okaasan no te ni nigitte iru" (The baby is holding the mother's hand), students thought that お母さんの手 (the mother's hand) was the arrival point for 握る"nigiru" (hold), and choose 二格 "ni kaku" (ni case) instead of ヲ格 "wo kaku" (wo case), and overgeneralization occurred.Similar problems also occurred with the verbs ほめ る "Homeru" (praise) and い じ め る "Ijimeru" (Tease).
The result that there was no meaningful difference between the experimental group and the control group may lead us to conclude that there is no problem with pattern practice like the control group.However, it was confirmed in follow-up interviews and follow-up classes that the experimental group's overall performance improved by making them aware of overgeneralization in follow-up classes, which shows it takes time for learners to acquire the characteristics of the language (Koyanagi, 2004) including acquiring the "argument" of verb.On the other hand, although the control group's post-class test results were good, their overall performance worsened after the follow-up tasks class.This is because, as Kellerman (1985) stated, learners' developmental curves are U-shaped, and there are times when their development appears to have regressed.
In future tasks, it will be necessary to look at the long-term aspects of the experimental group's exposure to the concept of the verb "argument" in class.

CONCLUSION
This research started from the starting point of incorporating the concept of verb "argument" into an experimental Focus on Form (FonF) class to see the effect on learners' acquisition of case particles.Statistical data based on class test results shows that there is not much difference between this trial and conventional methods in the short term.
Based on this, in future research, it is necessary to first look at the long-term effects on learners who have learned the concept of verb kou "argument".One method is to incorporate the research of Maarif (2021), which is the starting point of this research.It is necessary to confirm whether the knowledge of case particles acquired through the concept of "argument" affects the understanding of the relationship between inside and outside of adnominal modifier clauses.

Table 2 :
Required types and numbers of class tests.

Table 3 :
Grouping of Subjects.

Table 4 :
Test scores for pre-class, post-class, and follow-up classes.

Table 5 :
Post-class P value.

Table 6 :
Follow-up class P Value.

Table 7 :
Number of incorrect answers to pre-class test question 1.

Table 8 :
Number of incorrect answers to pre-class test question 2.
Table 11 contains a comparison of incorrect answers for preclass test question 1, number 8, and post-class test question 1, number 7.

Table 9 :
Number of incorrect answers to post-class test question 1.

Table 10 :
Number of incorrect answers to post-class test question 2.

Table 13 :
Follow-up class question 1 test incorrect answer frequency (people).

Table 14 :
Follow-up class question 2 test incorrect answer frequency (people).