1、主将从现是指在时间状语从句、条件状语从句和让步状语从句中,如果主句是一般将来时,从句用一般现在时替代一般将来时。
如: When I grow up, I will be a nurse and look after patients/ I want to be a nurse and look after patients.
2、主祈从现是指如果主句是祈使句,从句用一般现在时。
如:Please let me know if he comes back.
3、主情从现是指如果句子中有情态动词,那么情态动词后加一般现在时的动词,即动词原型。
如:If you feel hungry ,you should eat something.
扩展资料:
主将从现在含有时间状语从句和条件状语从句的主从复合句中,如果主句的时态是一般将来时,那么从句要用一般现在时。
例如:I will tell him about it when he comes.
If it is fine tomorrow, we will go outing.
如果if的条件状语从句遇到变换间接和直接时 , 祈使句应用not....to....
如:Don't close the window if the rain stops, she said.
→She said not to close the window if the rain stops.
I will walk to school if it doesn't rain tomorrow.这是主将从现,主句是I will walk to school 中有“will”,表示将来,句中如果有“am/is/are going to"也是一般将来时态,it doesn't rain是从句,句中的”doesn't“很好的体现出这是一般将来时态,tomorrow是时间状语,通常由”if“引导的句子是主将从现
Please let me know if he comes back.这是主祈从现,主句是Please let me know中含有”please“是祈使句,祈使句一般开头是以do 、let、don't、never、to do开头,he comes back是从句,comes说明是一般现在
If you feel hungry ,you should eat something.这是主情从现,you should eat something是主句,句中的”should“是情态动词,情态动词常用的有can、may、must、should,you feel hungry是从句,一般现在
总结:主要看句中有没有if,when,as soon as……这些词有时代表主将从现,主祈从现,主情从现,注意:when有时可以和延续性动词连用,也可以和短暂性动词连用,例如:when Iwas get there,he was singing in the KTV.