英语if用法归纳初二
扩展资料
if从句和虚拟语气:
1. 当if后面接一般现在时的动词时,表示对将来的'一种推测. if sb do sth sb will/shall do sth. If you go with me, you shall be rewarded.
2. 当if后面接一般过去时的动词时,则是一种虚拟语气. if sb did sth sb would/should do sth. If I didnt make that mistake, I wouldt have suffered such a failure.
3. 当if后面接什么时态都可以时,if为“是否”的意思,句子为宾语从句. sb do sth if sb do sth. He said if rain was stop. 由if引导的条件状语从句,时态应该是主将从现,就是说主句用一般将来时,而从句用一般现在时表示将来。
例如 If it doesnt rain tomorrow, I will visit my former school. 这里从句就用一般现在时。当然if引导的从句也可以用虚拟语气,例如 If I got up early in the morning, I wouldnt miss the train.