—Let's go to school.
—_________.[ ]
A. OK
B. Let's
C. Sorry
答案：A
—Can you ________ him studying hard?
—No, I can't. He never studies hard. [ ]
A. stop
B. prevent
C. keep
D. warn
关于钢结构的特点的描述，下了说法不正确的有（）。
A.钢材强度高
B.钢材塑性、韧性都好
C.钢结构自重较轻
D.钢材耐火
E.钢材耐腐蚀
