‘whether’ and ‘if ’在用法上有哪些区别?

2个回答

  • whether和if的用法区别 whether与if作“是否”讲,在用法上有相同之处,也有不同之处.一、相同之处.1.whether和if都能引导宾语从句,常置于see,ask,learn,tell,wonder,doubt,find out等动词之后.如:He asked me whether/is I could help him.I want to know whether/if he lives there.2.whether和if都可用it作形式主语从句中.如:it's uncertain whether/if he'll come this evening.3.在be uncertain/doubtful之后,常用whether引导宾语从句,有时也可以用if,如:We are uncertain whether/if Mary will come.二、不同之处.1.whether可置于句首引导主语从句,而if不能.如:___the 2000 Olympic Games will be in Beijing is not known yet.A.whether B.If C.Whether D.That 答案是C.2.whether可用在介词之后,引导宾语从句,而If则不能.如:Success depends on whether we make evough effort.3.whether可引导表语从句,if则不能.如:The puestion is whether it is not worthdoing.4.在名词之后引导同位语从句时,用whether而不用if.如:The puestion whether the students answered correctly should be decided by the teacher.5.whether后可接不定式,而if不能.如:Please tell us whether to go or stay here.6.在有些动词(如discuss)之后,只能用whether,而不用if引导宾语从句.如:We discussed whether we should close the shop.7.在引导否定概念in宾语从句时,只能用if,而不用whether.如:he asked me if I hadn't finished my work.