if 从句和虚拟语气

来源:学生作业帮助网 编辑:作业帮 时间:2024/03/29 16:45:11
if 从句和虚拟语气

if 从句和虚拟语气
if 从句和虚拟语气

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 didn't make that mistake, I would't 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 doesn't 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 wouldn't miss the train.

找本语法书详细看一下比较好。不懂再详细问。