新概念英语第二册53-04

Lesson 45 A Clear Conscience

learn 得知

The whole world learnt... 全世界都知道...

while doing 是一个省略形式

这种情况应具备两个条件

1. 这个动作的主语跟主句的主语一样.

2. 这句话一定要是进行时态

这句话完整的应为：

while he was taking ...

must have been done

must have done 表示对过去的推测

must have been done 表示对过去被动的推测

三种表示一段时间以后，另外一件事情发生的方式:

1. ... passed and then

2. some time later

3. some passed before

wrap up 包裹

It had been wrapped up in newspaper by somebody.

half the money

half an hour

half a year

together with = with 介词短语作状语，表示随它一起的还有 ......