国家按行政建制设立的直辖市、市、()称城市。
A、县
B、区
C、乡
D、镇
参考答案:D
We had _______ 8-day holiday during this National holidays, but some of us felt unhappy because of _________heavy traffic on the highways.
A.an, the
B.a, the
C.a, a
D.an, a
起重机的特点?