问题:
Do they work _____ the day time or _____ night?
A.at; in
B.in; at
C.on; at
D.at; on
Do they work _____ the day time or _____ night?
A.at; in
B.in; at
C.on; at
D.at; on
A.at; in
B.in; at
C.on; at
D.at; on
参考答案: