题干

The chemistry teacher required the students ________ more attention _______ the lab clean.

A:to pay; to keep

B:to paying; to keeping

C:to pay; to keeping

D:paying; keeping

上一题 下一题 0.0难度 选择题 更新时间:2018-12-30 10:46:42

答案(点此获取答案解析)

C