小编给大家带来公共英语考试二级口语辅导练习(15)，希望对大家有所帮助。下面就请大家跟随小编的脚步一起来看看吧。希望各位备考公共英语二级的小伙伴们都能顺利上岸~
　　用一般过去时代替完成时
　　1)两个动作如按顺序发生，又不强调先后，或用then，and，but 等连词时，多用一般过去时。
　　When she saw the mouse，she screamed.
　　My aunt gave me a hat and I lost it.
　　2 ) 两个动作相继发生，可用一般过去时;如一、个动作需要若干时间完成，用过去完成时。
　　When I heard the news, I was very excited.
　　3)叙述历史事实，可不用过去完成时，而只用一般过去时。
　　Our teacher told us that Columbus discovered America in 1492.
　　过去完成时典型例题
　　The students ___ busily when Miss Brown went to get a book she ___ in the office.
　　A. had written, left
　　B. were writing, has left
　　C. had written, had left
　　D. were writing, had left
　　答案D. "把书忘在办公室"发生在"去取书"这一过去的动作之前，因此"忘了书"这一动作发生在过去的过去，用过去完成时。句中when表示的是时间的一点，表示在"同学们正忙于……"这一背景下，when所引导的动作发生。因此前一句应用过去进行时。
　　注意：
　　had no … when还没等…… 就……
　　had no sooner… than刚…… 就……
　　He had no sooner bought the car than he sold it.