The purpose of the study is to provide a guideline for the pedagogical approaches to teach Thai students the grammar of the Chinese adverbs "zai" and "you". Questionnaire results revealed that the reasons for the misuse of "zai" and "you" by Thai university students can be classified into three causes: (1) "zai" and "you" suggest repeatedness and both of them can be literally translated into the Thai /Ik/,(2) the complicated semantic characteristics of "zai" and "you" themselves and (3) the situation in the process of "zai" and "you" acquisition being not completed. In terms of pedagogical approaches, this study presents an appropriate sequence for the learning of the adverbs "zai" and "you" in Mandarin Chinese according to the frequency of occurrence and the frequency of error. Furthermore, the study suggests that teachers should first teach the grammar points that are used more frequently and have more straightforward semantics familiar to most students. Those used infrequently and likely to cause errors should be taught later. (Contains 5 tables and 3 footnotes.)