2)act for 代理(某人职务)，代为(处理某事
Please act for me during my absence.
我不在时请代理我处理事务。
3)act out (用手势和语言)表演出来
Let’s act out the story of the three bears once more.
让我们再把这三只熊的故事表演一次吧。[heavy] traffic。
4) act on (upon) 对……起作用，对……有效
Alcohol acts on the nervous system.
酒精对人的神经系统有影响。[heavy] traffic。
5) in the act (of) 当场，正在动作时
He was caught in the act (of reading my private letters).
他(在读我的私信时)被当场抓住。
【练习】
1、The crowd cheered wildly at the sight of Liu Xiang, who was reported _____ the world record in the 110-meter hurdle race. (07辽宁)
A breaking B having broken
C to have broken D to break
