英语六级语法知识: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;如第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.