1. 根据语境，从方框中选择恰当的单词填空，注意形式变化。

interesting,   lesson,   to,   half,   because

1. （1） I don't like this room it's too small.
3. （2） I have four this afternoon.
5. （3） This is a(n) book. Read it, please.
7. （4） of the chairs in this room are blue.
9. （5） It's five eight. Let's go back to the classroom.