汽车起重机按重量分为轻型、中型、重型三种，下列规格的起重机中，属于中型起重机的是（）。
A．12t
B．16t
C．40t
D．50t
参考答案：C
Lots of people in our city _____ the old and the disabled. They usually offer their seats to them on buses or help them cross the road.
A. care for .
B. take care
C. agree with
D. take pride in
属于胃癌癌前疾病的是（）。
A.残胃炎
B.肠型化生
C.慢性萎缩性胃炎
D.异型增生
E.胃溃疡
