否定句型练习 2

把肯定句改为否定句。因为每句已经有助动词，所以不需要加 “to do” 助动词。请遵守英文语法各方面的规则。

按照这个例子来回答：

原句：Jack Black is playing his new guitar.
答案：Jack Black is not playing his new guitar.

1. Susan is washing her face.

2. Robert has gone skiing.

3. Eric has listened to jazz music.

4. Lili was eating broccoli.

5. Mom is telling a funny story.

6. Sally’s dog has made a mess.

7. Grandpa is yelling at the birds.

8. They have sung the song.

9. David is baking a pineapple pizza.

10. Jack and Sam have done it.