问题补充:
Many teens don’t get enough sleep because they have too much homework to do, which them up at night.
A. makes
B. breaks
C. turns
D. keeps
答案:
A. makes
B. breaks
C. turns
D. keeps
解析:考查动词辨析:A. makes制作B. breaks打破C. turns转D. keeps保持,keep up是词组“维持,不低落”这里是“不能睡觉”,句意:很多年轻人没有足够的睡眠,因为作业太多,这使他们晚上不能睡觉。选D。