哪些动词后通常只用 whether
来源:学生作业帮 编辑:搜搜考试网作业帮 分类:英语作业 时间:2024/07/28 12:51:00
哪些动词后通常只用 whether
![哪些动词后通常只用 whether](/uploads/image/z/7091280-0-0.jpg?t=%E5%93%AA%E4%BA%9B%E5%8A%A8%E8%AF%8D%E5%90%8E%E9%80%9A%E5%B8%B8%E5%8F%AA%E7%94%A8+whether)
一、相同之处.\x0d1.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.\x0d如:He asked me whether/is I could help him. I want to know whether/if he lives there.\x0d2.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.\x0d3.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.\x0d二、不同之处.\x0d1.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.\x0d2.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.\x0d3.whether可引导表语从句,if则不能.如: The puestion is whether it is not worthdoing.\x0d4.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.\x0d5.whether后可接不定式,而if不能.如: Please tell us whether to go or stay here.