Investigation into Japanese learners'acquisition order of major grammatical morphemes using error-tagged learner corpus EMI IZUMI•õ,KOYOTAKA UCHIMOTO•õ nd HITOSHI ISAHARA•õ In foreign language education,it is important for teachers to know their students' acquisition order of major linguistic items in the target language.There have been a lot of studies done for revealing natural sequence in second language acquisition since 1970's,and it is one of the established ideas that major grammatical morphemes are acquired in the common order by learners across different backgrounds such as their L1,ages,or learning environments(The fist hypothesis).

Language learners use various kinds of communication strategies to compensate their imperfect knowledge on the target language,especially vocabulary.Paraphrase is one of the important strategies.It must be worth doing to teach how paraphrase in foreign language communication can be done more effectively.In vocabulary teaching, if the certain word entry is introduced with several other relevant words or expressions,it would be quite helpful for learners to do more successful paraphrase.In this research,we have done the experiment to see how this kind of expanded teaching of vocabulary or expressions can be accomplished by using diverse expressions extracted from the spoken corpus of Japanese learner English,"The NICT JLE (Japanese Learner English)Corpus".In the experiment,we first made the keyword list based on the small amount of English native speakers' utterances by hand. Then,we automatically extracted the diverse expressions which describe the particular matter from the learner data to make the learners' expression list.We have