1 . It is time for lunch
2 . Turn back the clock
3 . You give an excellent speech，I mean it
4 . (在非限制性定语从中。
例如：
5 . 他刚来，她就开始抱怨。
6 . Q: What is Jim going to do tonight?
7 . ( 先行词被only， no， any， all，等词修饰时。例如：
8 . Tom is not so tall as his brother (Tom is less tall than his brother
9 . W: It is said he got the flu and stayed in bed all day
