It is rather hot in the room. They( )have turned off the air conditioner a few hours ago.
A.正确答案Ccould
B.ought
C.must
D.should
It is rather hot in the room. They( )have turned off the air conditioner a few hours ago.
It is rather hot in the room. They( )have turned off the air conditioner a few hours ago.
A.正确答案Ccould
B.ought
C.must
D.should