文档介绍：whether与if的区别
1. 引导宾语从句时可以互换。
eg: He asked whether they needed some more tea.
She asked Lucy if she could go and get some.
I don't know whether /if she will come.
2. 但在下列几种情况下,不可用if 代替whether。
1)当whether 与or not连成词组时。
eg: I don't know whether they will come for our help or not.
2)whether与不定式连用时。
eg : She hasn't decided whether to go or not.
3)whether引导的从句放在句首时。
eg: _______this is true or not, I can't say.
______ we'll go camping tomorrow depends on the weather．
4). 当whether引导的从句做介词的宾语时，不能用if替换。
eg: They are talking about_______ they will go to the Summer Palace.
He doesn't think the question of ____ they are men or women is important．
5).在引导主语从句、表语从句、同位语从句时只能用whether，不能用if.
1)．The question is ____  the film is worth seeing．
2)． _______we will hold the meeting depends on the weather.
3). It was uncertain ______my playmates would come(or not).
4). There is some doubt ______John will come on time.