8. This is a non-smoking area,so you   (不得在这里抽烟) .

7. If you   (没给我打电话) ，I wouldn’ t have known aboutthe party.

6. He is wearing a gold ring on his fourth finger. He   (一定结婚了) .

5. This is our gift to you. You        (不必把它还给我们) .

4. Since the teenagers were partying very loudly,they (不能听见) the door bell.

3. As his leg was injured,John (不能比赛) for the next couple weeks.

2. Neil wouldn't have had the accident if he   (没有突然刹车) .

1. There is another bus later,so we     (不必上这辆) .

12. But for the kind lady,I (wander) in the street now.

11. If I were you,I (go) to the beach instead of going to work.