储气罐压力短时间急剧降低的原因可能是()、()。
参考答案:空压机故障;漏气
What's the ________ of having a public open space where you can't eat, drink or even simply
hang out for a while?[ ]
A. sense
B. matter
C. case
D. opinion
After the class was over, the student apologized ___ the teacher ____ his coming late.
A.for; to
B.to; with
C.with; to
D.to; for