（一）定语从句复习
用定语从句把下列句子连接成一个句子
1. The book is mine. He is reading the book.
The book (which/that) he is reading is mine.
2. I like the girl. The girl is wearing a red skirt.
I like the girl who is wearing a red skirt.
3. She is the student. We saw her yesterday.
