This study investigates the acquisition process of English relative clauses as a second language, this paper first examines Korean High School students' comprehension of 9 Types of English relative clauses. Fifty High School students were tested in this experimental study. Also, to see the amount and the diversity of relative clause types in English textbooks, Eleven textbooks for 1st-year and ten textbooks for 2nd year-students were investigated. As a result, Korean L2 learners of English, differently from previous L1 studies, have shown the developmental order as SO>PO>PP>OO>SP>OS>OP>SS>PS Type. This shows that embedding depth as well as Korean word order seem to affect students' comprehension of English relative clauses. The results also show that the distribution and the frequency of relative clause Types in English textbooks do not reflect Korean students' developmental process properly.
Wooyoung Cho (Sat,) studied this question.