时间状语从句的"改头换面"：

..., when/after/before ...。 (...代表“完整的句子”)

e.g.  当人们遇到困难的时候，他们常常会选择放弃正在做的事情。

常见的“中国方式”的翻译可能是这样的：

When people meet hardships, they usually choose to drop the business they are coping with.

这个句子从结构上，以及选词上都可以说是非常到位的，但是有“一个问题”在于作者没有考虑到“句子的主次”。 由于when所引导的句子是从句，因此名词people应该被转移到主句上。而且先后次序可以调整。即：

People usually choose to drop the business they are coping with when they meet hardships.

而且，根据英文句子对于“concise”的要求，更好的处理是将 作为代词的they去掉，与此同时将are转换为分词being，构造“分词作状语”的效果。

People usually choose to drop the business they are coping with when meeting hardships.

OR

Meeting hardships, people usually choose to drop the business they are coping with.

练习：

1、在现代大学生完成学业即将进入开始工作前，他们不得不面对激烈的社会竞争。

2、当人类第一次到达月球，他们已经创造了一个奇迹并真正改变的历史。

Sample Answers:

1. Modern college students have got to face fierce competition in the community when finishing their curriculum immediately getting to work.

2. People have made a miracle and  a history when arriving at the moon.