1. act vt.扮演，表演，举止，表现，起作用，有功效，行动 n.行动，行动，法令，条例
In the play, Tom will act as the part of Hamlet.
在剧中，汤姆将扮演哈姆雷特。
This time, a local villager acted as our guide.
这次，一个当地的村民担当向导。
Everyone in the mission should act on the plan.
在该任务中，每个人都应该按计划行动。
Does the drug take long to act (on/upon the pain)?
这药是否需要很长时间才能起（止疼）作用？
It’s a noble act to offer help to those who are in trouble.
帮助那些处在困境中的人是一种高尚的行为。

2. brain n. 头脑（可数名词）
智力（不可数，可数多用复数形式）
最聪明的人（可数，多用复数形式）
It doesn’t take much brain to work out this problem.
要解决这个问题不需费多大脑筋。
You need brains as well as brawn to do this job.
这项工作耗神又费力。
We have the best scientific brains in the country to work on the program.
我们有国内最优秀的科技人才从事这个项目。

3. response n.回应，反应；回答
They did it in response to external pressures.
他们是迫于外界压力才做这件事的。
The product was improved in response to customers' demand.
应顾客的要求，我们改进了该产品。
They sent out signals for help, but there was no response.
他们发出求救信号，但是没有得到回应。
Our appeal met with no response.
我们的呼吁没有得到 任何回应。 

4. somehow adv.不知道为什么，以某种方法，设法
Somehow I felt as if I had been cheated.
不知怎么，我好像有一种被骗了的感觉。
I think he is right but somehow I'm not completely sure.
我想他是对的，但我觉得并不完全有把握。
Somehow or other I was able to solve the problem myself.
我总算能自己解答那个问题了。
I can't see how, but we'll have to reach an agreement somehow.
我不知怎样做，但我们总得设法达成协议。