1. was used to → used to， used to +动词原形表示过去的习惯， be used to+名词/动名词表示习惯的持续。

10. The doctor advised me giving up to smoke.

　　 注 释

9. You had better not to go there.

8. Smiling graciously, my offer was accepted by him.

7. You should avoid to keep company with such people.

6. It is difficult to make yourself understand in English.

5. His father would not let him to go.

4. He always enjoys to read a detective story.

3. We hear it say frequently that what present-day men most desire is security.

2. He has never been heard speak ill of others.