英语六级语法必备之比较while,when,as

 　　1)as¹, when 引导短暂性动作的动词。

　　Just as / Just when / When I stopped my car, a man came² up to me.

　　2)当从句的动作发生于主句动作之前，只能用when 引导这个从句，不可用as 或 while³。

　　When you have finished⁴ your work, you may have a rest.

　　3)从句表示"随时间推移"连词能用as，不用when 或while。

　　As the day went on, the weather got⁵ worse⁶.

　　日子一天天过去，天气越变越坏。

1 as   

conj.按照；如同

参考例句：

• He got work in a hotel as a waiter.他在一家旅馆找到了当服务生的工作。
• In the hotel,the old men were drinking away as usual.在旅馆里，这些老人和往常一样喝个不停。

2 came   

v.动词come的过去式

参考例句：

• I was surprised why he came here so early.他为什么那么早到这里，我很惊奇。
• The doctor came in time to save his life.医生及时来抢救他的生命。

3 while   

conj.当…的时候；而；虽然；尽管 n.一会儿

参考例句：

• In a short while,the cat ate up the fish.不久，那只猫便将鱼吃个精光。
• He teaches English in the school all the while.他一直在这所学校里教英语。

4 finished   

adj.完成的，精湛的；v.动词finish的过去式和过去分词

参考例句：

• We finished up everything there was on the table. 我们把桌上的东西全吃完了。
• We can certainly have the job finished on time.我们肯定能按时完成任务。

5 got   

v.(get的过去式)得到，猜到，明白

参考例句：

• I just got some bad news.我刚得到一些坏消息。
• I have got far too much work to do.我要做的事太多了。

6 worse   

adj.更坏的，更差的；adv.更坏，更差

参考例句：

• I have even worse news for you.我有更坏的消息告诉你。
• The weather got worse during the day.白天天气更坏了。