--- Tommy is planning to buy a car.
--- I know. By the time he returns from abroad, he enough for a used one.
A. will have saved
B. saves
C. had saved
D. will save
网友回答
(答案→)A. will have saved
B. saves
C. had saved
D. will save
解析：考查时态：句意：--Tommy正计划买个汽车。--我知道。到他国外回来的时候他将攒足够买一辆二手车的钱。By the time引导的是时间状语从句，用一般现在时代替一般将来时，所以主句应该是将来范畴的时态，而且时间状语是by the time连接的，主句用将来完成时。选A。