<正> whether 和 if都可作“是否”讲,它们在使用上有何异同?请先用 whether 或 if 填空,然后参看答案及简析: 1.I want to know_______she has gone to the front. 2.We wondered______that man was a spy or not. 3.It hasn’t decided_______these foreign guests willvisit our college. 4.I don’t know______or not Tom has passed theexamination. 5._______it is true remains a question.