放射工作人员主要接触的射线是()
A.γ、X射线
B.α、β射线
C.中子
D.α、γ
E.以上都不对
参考答案:A
— What do you think of your teacher?
— He often _____ funny jokes and always _____ us _____. [ ]
A. speaks, makes, laugh
B. tells, makes, laugh
C. says, makes, laughing
D. tells, makes, to laugh
某场上持球队员被对方严密防守,在()内没有传、投、滚或运球时,应判违例。
A、20秒;
B、5秒;
C、24秒;
D、8秒。