They don't know if the doctor_____here.if he _____ ,they will meet him at once
A.will come ,comes B.will come ,will come C.comes ,will come D.comes,comes
答：A
译：他们不知道医生来不来这里.如果他来的话,他们就会立刻去见他.
析:第一个if=whether引导宾语从句,该用一般将来时还得用一般将来时.后面的if从句是条件状语从句,用现在时表将来.