【简答题】乘客服务区指:包括 ( )、( )、( ) 、( )、( ) 在内所有会发生乘客服务行为和处理乘客事务行为的区域。
【单选题】I have __________ the problem for two hours, but I haven't __________. [ ]
A.
worked on, worked out it
B.
worked at, worked it out
C.
worked on, worked it out
【单选题】—I failed again. I wish I ____ harder. ---But you ____.
【单选题】I worked on the problem ____ a long time and I worked it out ____ myself ____ last. [ ]