if后面接什么时态

if有如果，倘若等意思，那么if后面接什么时态呢?下面是本站小编为你整理的if后面接的时态的相关资料，希望大家喜欢!

　　if后接的时态

一般现在时

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...

　　if从句的时态

if有两个意思：“是否”和“如果”.

当做“是否”讲时一般引导宾语从句,时态依据时间状语来做决定,

如：I don't know if he will come tomorrow.

当做“如果”讲的时候,又分为两种情形：

1.真实性条件状语从句,此时遵循“主将从现”原则,即主句用将来时,而if条件状语从句用一般现在时来代替将来时.

如：If it doesn't rain tomorrow,I will go shopping with my friends.

2.虚拟性条件状语从句,初中阶段常接触对现在和对将来的虚拟,此时主句多用过去将来时(would+动词原形),而从句用一般过去时(V-ed).

如：If I knew his telephone number,I would tell you.

　　if从句的三种用法

1、主将从现 (主句为一般将来时,从句为一般现在时);

eg:If it rains(从句) ,I will stay at home(主句).

=I will stay at home if it rains.

2、主句含有情态动词 (must、may、can etc.)从句为一般现在时;

eg:If you drive too fast ,you may have an accident.

=You may have an accident if you drive too fast

3、主句为祈使句,从句要用一般现在时态;

eg:Don't play computer games if you don't finish your homework.

备注：

1、If 于句首时中间用逗号隔开,主句后不用逗号.

2、if 可用unless(除非...) 替换ss= ...

3、注意虚拟语气 主句和从句都为一般过去式

eg:If I was a bird ,I could fly.(事实我不可能是鸟)