—Why do you collect so many old bikes?
—I will have them ______ and give away to the children who don't have bikes.

【正确答案】 C

【答案解析】 本题考查动词词组的辨析。句意：——你为什么收集这么多旧白行车?——我想要把它们修好后送给那些没有自行车的孩子们。use up意为“用尽，用完”；give up意为“放弃”；fix up意为“修理”；set up意为“建立”。所以答案为C项。