按照金属学的理论,含碳量小于0.8%的钢是()。
A.亚共析钢
B.共析钢
C.过共析钢
参考答案:A
My father is usually on _______ duty in his office every _______ few days.
A.the;a
B./; /
C./;a
D.a; /
温带多雨带的降水类型多为:( )
①地形雨 ②对流雨 ③锋面雨 ④雷阵雨 ⑤气旋雨 ⑥台风雨.
A.①③⑤
B.②④⑥
C.①④⑤
D.③⑤⑥