The purpose of this article is to illustrate an approach that can be used to describe and organize the content in the area of teaching grammatical knowledge. This article proceeds as follows. First, it points out the latent problem with a framework for task-based language teaching in the English as a Foreign Language (EFL) environment, and suggests the need for an explicit grammar teaching. In this article, the main purpose of foreign language teaching is considered to be the development of communicative language ability in the language concerned. It seems that this is much the same objective of the Course of Study for foreign languages or several approaches proposed by second language acquisition studies. But both are different in that the latter basically presumes syllabus content would be specified in terms of learning activities or tasks. This article suggests that apart from language activities, it is necessary to teach grammar explicitly with reference to the framework for foreign language teaching curriculum which is based on the theoretical consideration of what constitutes communicative language ability in a foreign language. Second, it points out that currently employed ways of teaching lack explanations of the syntactic and semantic character of the English comparative expressions, reviewing some text books and grammar teaching books. Third, it proposes a basic structure of the teaching process, based on a theoretical examination of the system of the English comparative expressions and on a hypothesis of a possible learning process on the part of the learners. And it extracts "a module of the teaching content" from it, viewed from what could be contrasted with regard to choosing an appropriate expression in context. Finally, it proposes an approach to organize the module as a lesson plan in consideration of the differences of three pragmatic aspects: ideational, interpersonal, textual rhetoric (cf. Leech 1980). According to the character of these aspects, each question in the lesson plan presented partly is designed to ask which expression is appropriate in the present situation. For example, when we are talking about our trip, and one person proposes going to Okinawa but you want to go to Seoul, then I think Seoul is nicer than Okinawa and I think Seoul is as nice as Okinawa is presented to ask which is appropriate to express your wish, not being in discord with them, namely, as a question of the interpersonal rhetoric.