14．be about to….when.　 　①正在。。。，突然。。。

　　 be doing….when..　　 ②正在。。。，这时。。。

13. should have done=ought to have done指过去的动作，“本该做而没做”

　 shouldn’t have done=oughtn’t to have done“不该做而做了”

12.not only…but also…连接并列的成分，还可以连接句子，若not only置句首，第一个句子倒装，而第二句语序正常。Eg..Not only do the nurses want to a pay increase, they want to reduce hours as well.

10. even if/though　 即使，纵然　 11。 as if/though 似乎，仿佛

9.hate/admit/avoid/consider/delay/enjoy/escape/finish/imagine/mind/miss/practice/resist/risk/suggest+doing

7. have difficulty in doing sth./with sth.　　 8. Sorry , I didn’t follow you.

5. Rock music is OK, and so is skiing.　　　　 6. with +宾语+宾补

4. I don’t enjoy singing, nor do I like computers.

3. He likes/loves/is fond of…　

2. It is important/impossible/easy/hard/necessary for sb. to do sth.