57、X射线机操作员应在了解X射线机相关指标定义的基础上,掌握X射线机是否符合( )的要求,以此判断X射线机是否处于( )工作状态。

19、In order to improve( ),passengers in tourist group,please line up in order according to the list of plane tickets.

18、A:( )

17、A: What’s the check-in time for my flight?

32、设备在1小时内能检查长度为1米的被检物的数量是( )的定义。

19、Sorry, sir, because( ),you can’t take it on board the plane.

18、You may get your( )at the check-in counter and then you have to go through the security check.

17、I am the( ) of the group.

16、A:What will happen to me if I refuse the security check?

15、A: Where’s your destination? B:( ).

68、X射线机材料分辨力用英文表示为( )。