— There'ssomeone knocking on the door. Who _____it be?— It must be Mary. She promised to be here at 8:00.
#62863
A
must
B
need
C
shall
D
Can
推荐题目
We ______ the difficulty together, but why didn't you tell me?
#63504
A
should face
B
might face
C
could have faced
D
must have faced
Mary ______ my letter; otherwise she would have replied before now. 
#63420
A
has received
B
ought to have received
C
couldn’t have received
D
shouldn’t have received
 ______ Tom be in his office so late at night ?
#74672
A
Can
B
May
C
Might
D
Must