本课教材分析：
Title: This is my sis ter.
Topic: The family
Functions: Introd uce peopl e :This/That is… These/Those are…,
Identi fy people: Is this /that …? Are these /those …?
Structures:
Demonstrati ves this, these, those, that
Subject pronouns I, he, she, they
Yes/No questions and sh ort answers
