本來(lái)whether與 if在賓語(yǔ)從句中意思差不多,
I wonder if...=I wonder whether...
I see if...=I see whether...
I ask if...=I ask whether...
I try if...=I try whether...
I don't know if...=I don't know whether
1.但是當(dāng)介詞后的賓語(yǔ)從句,只能用whether,不能用if
It depends on whether you will agree.這取決于你是否同意.
2.在動(dòng)詞不定式前只能用whether,不能用if.
I wonder whether to stay here another week.
我想是否在這兒在呆一周.
3.用or表示選擇概念時(shí),用whether,不能用if.
He wondered whether he should wait for them or go on.
He wondered whether she liked it or not.
他不知道是等他們,還是繼續(xù)往前走.
4引導(dǎo)表語(yǔ)從句只能用whether,不能用if.
The problem is whether we will go there by bus or by plane.
另外whether還可以引導(dǎo)主語(yǔ)從句,主語(yǔ)從句不用if