Abstract: The paper, within the framework of R. W. Langacker's Cognitive Grammar, attempts to propose some principles and strategies for the teaching of English grammar, with reference to a case of child language acquisition and the author's own teaching experience. The paper holds that the usage-based teaching of English grammar should teach the students what the natives say and speak in the daily communication, integrate grammar with meaning and compare English with Chinese when necessary. The teaching should be conducted from the bottom to the top.