if从句的时态格式有什么要求吗?主句指哪半句,从句指哪半句?回答者一定要对英语驾轻路熟,敢保证所回答的是正确的!答后封赏,
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if从句的时态格式有什么要求吗?主句指哪半句,从句指哪半句?回答者一定要对英语驾轻路熟,敢保证所回答的是正确的!答后封赏,
if从句的时态格式有什么要求吗?主句指哪半句,从句指哪半句?
回答者一定要对英语驾轻路熟,敢保证所回答的是正确的!答后封赏,
if从句的时态格式有什么要求吗?主句指哪半句,从句指哪半句?回答者一定要对英语驾轻路熟,敢保证所回答的是正确的!答后封赏,
if引导两种条件句:真实条件句和虚拟条件句.
真实条件句:
If he has written the letter,I'll post it.
If I have time(表示条件的是从句),I'll come over to see you.(由条件导致的结果就是主句)
在真实条件句里,从句用一般现在时表示将来时,主句用一般将来时.
虚拟条件句:
If I had enough money(从句),I would buy a computer(主句).
如果我有钱,我要买一台电脑.(但我没有)
虚拟语气用于表达不可能实现的事情.虚拟条件句又有现在情况,将来情况,和过去情况.
1)表示现在或将来:
条件从句中的谓语是相当于过去时的形式,主语谓语用would+动词原形:
If I had a map I would lend it to you.如果我有地图我就借给你.(但我没有)
If I dyed my hair blue everyone would laugh at me.如果我把头发染成蓝色,谁都会笑我的.(当然我不会干这样的傻事)
2)表示过去:
条件从句中的谓语用过去完成时,主句的谓语动词要用would have+过去分词 :
If I had known that you were coming,I would have met you at the airport.如果我知道你要来,我就去机场接你了.
If anything had happened,he would have let us know.如果发生了什么情况,他在就通知我们了.