—Listen ! Helen is singing in the next room.—It _______ be Helen. She has gone to Beijing.
#74851
A
can’t
B
mustn’t
C
may
D
should
推荐题目
---Can you play the guitar?---________.
#74839
A
No,I can
B
Yes,I can’t
C
I can play the guitar
D
No,I can’t
—_______ do you clean your room?— Every day. 
#77537
A
How long
B
How many
C
How often
D
How soon