I cried whether my heart would break 这里的whether 为什么要用whether

I cried whether my heart would break 这里的whether 为什么要用whether Do you know whether I could pass the exam? 为什么whether后面用的是co Whether breaks your heart whether we will和whether we would I don't know__he will come tomorrow.这里为什么用if而不是whether He asked me whether I could help him.这里为什么用could whether great changes will take place为什么用whether 引导 请问这里whether 引导的什么从句 为什么只能用whether I did not know whether my plan would work or not,but I decid i think造句用that,whether,if i doubt whether he is telling the truth.为什么要用is telling,不用te