Mr.Li,our teacher will leave our school this year.(Mr.Li,our teacher 是主语同位语)
He is strict that he doesn't any students say a word in the class.(that引导的标语从句)
I want to know whether you will come this afternoon?(whether引导的宾语从句---句子做宾语)
That he won't come to us makes us dissapointed.(that引导的主语从句===句子做主语)
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