语法if的问题主句是一般现在式,重句是什么式?例：Usually,if they do not give us a tr

语法if的问题主句是一般现在式,重句是什么式?例：Usually,if they do not give us a tr we can play a trick on them if they do not give us a treat.【 If they do not give us a teat,we can play a taick on them.中文 同义句转换：we can play a trick on them if they do not give ustrea Please buy that lantern.同义句Please but_____ They give us a tr 虚拟语气,对将来的,if they were to do,否定是if they were not to do嘛 英语条件句的时态问题都说条件句的主句用一般将来时从句用一般现在时,可是这里主句却用了一般现在时：if i do some if的语法问题if领导的条件状语从句,主将从现,我想问如果是If开头的句子,哪半是主句,哪半是从句如果是If在中间的句子 we play a trick if they don't give us a treat.对play a trick if they don't give us a treat ,we can play a trick on them翻译 把They usually give us a treat of some candies.改为同义句. They asked ____ or not they could help us .A.if B.whether