—Mum, would you please buy me an MP5 player?
—If you can help do the dishes the whole vacation, you have one as a reward.
A. must
B. need
C. would
D. shall
网友回答
A. must
B. need
C. would
(答案→)D. shall
解析：选D。句意：——妈妈，你能给我买一个MP5吗？——如果整个假期你能帮着做家务的话，你可以得到一个(MP5)作为奖励。shall此处表允诺。must必须，need需要，would愿意，均不符合语境。