第1个回答 2011-05-01
whether可以引导从句,作主语、表语或同位语,而if不能。如:
正: It was uncertain whether he would come.
误: It was uncertain if he would come.
正: His first question was whether Tom had arrived yet.
误: His first question was if Tom had arrived yet.
正: We must consider the question whether we will take these measures.
误: We must consider the question if we will take these measures.
第2个回答 2011-05-01
If也有是否的意思,老师讲过,当 if 和whether同时出现并表“是否”时,必定选whether,能用if的地方一定能用whether,因为whether应用范围比较大,涵盖了if。
第3个回答 2011-05-01
if做是否的意思只能用于状语从句,主语、表语从句只能用whether表示是否。
第4个回答 2011-05-01
作“是否”讲的时候,用whether 不用if