问题
选择题
The light is still on. He _____ to turn it off when he _____ the room.
A.may forget: leave
B.must have forgotten : left
C.may forget : have left
D.could have forgotten : left
答案
答案:B
The light is still on. He _____ to turn it off when he _____ the room.
A.may forget: leave
B.must have forgotten : left
C.may forget : have left
D.could have forgotten : left
答案:B