【题目】选词填空。
am is are
1.Mom: ______ Sam doing his homework?
Amy: No, he isn’t.
2.Mom: Are you tidying your room now?
Sam: Yes, I ______.
3.Mom: Sam , what ______ you doing?
Sam: It’s a secret.
4.Mom: ______ you drawing a picture, Amy?
Amy: No, he isn’t.
【答案】1.Is 2.am 3.are 4.Is
【解析】略
