The Classification of Interlingual and Intralingual Interference in Learners' Grammatical Errors Made by Indonesian Foreign Learners

This research studied the types and sources of errors made by foreign learners of Indonesian; the errors were specified into two categories: interlingual (mother tongue) and intralingual (learning strategies) interference which follow the strategies proposed by James (1998). As Sugiyono (2007-as cited in Setyo Sari, 2011) suggested the whole population theory, two students from unit five of IMLAC (Indonesia Multi-Language Acquisition Center) participated in this research. In regard to data collection, the writer used copies of students' work to be the subject of analysis. The purpose of this study is to reveal the most significant interference between interlingual and intralingual as well as the most evident source of errors. Throughout the research, the finding has uncovered that intralingual interference is more significant than the interlingual one; this result is in line with the previous research done by Husada (2007). Moreover, for future researchers, the writer recommends improvements in increasing the number of paticipants and expanding the target-sampling length which would present a more reliable and representative conclusion