McGloin (1989) points out that intermediate- and advanced- level students of Japanese often make grammatical mistakes because of "their inability to differentiate the usages of two or more similar grammatical forms which do not have obvious corresponding distinctions in English." I believe that this problem is due to the fact that students are trained to focus on sentence-level grammar despite the fact the Japanese language is discourse-sensitive and context- dependent (Ikegami 1989; Maynard 1998). For example, 'to yuu' such as in examples below is profusely used in Advanced-level reading materials such as newspapers, essays, and novels, yet few Japanese language teachers are aware of its discourse functions and thus cannot fully explain its use.
Tanaka-san ga kekkon-shita (to yuu) hanashi
Mr./Ms. Tanaka NOM got-married (COMP) story
"The story that Mr./Ms. Tanaka got married" As a case study to illustrate the importance of discourse grammar, this paper will discuss the discourse functions of "to yuu" and point out its implications to the teaching of Japanese as a second/foreign language.
First, I will clarify the relationship between 'to yuu' and the internal structure of its modifying clause. In so doing, I will examine in detail the contexts where speakers/readers deliberately include or exclude optional 'to yuu' and discuss the effect of such choices. Then, I will discuss how Japanese language instructors may apply the linguistic findings of optional "to yuu" in the classroom: it is important that non-linguist language teachers understand the discourse functions of "to yuu" to help their students master Japanese more effectively and efficiently. As a conclusion, I will emphasize the importance of discourse grammar and point out how it will help bridge the gap between correct sentence grammar and natural and effective usage.