Mary _______ her mother with the housework, but she didn’t.  
#63072
A
must have helped
B
ought to have helped
C
must help
D
should help
推荐题目
My new pen ______. Who ______ have taken it?
#62850
A
has been disappeared; can
B
has disappeared; could
C
is missing; should
D
has been lost; may
Mr Black   be at home because she called me from England just now.
#76189
A
mustn't
B
isn't able to
C
can't
D
may not
 —Why are you late again?—Something happened to our friend Wang Fei. I _____ to help him.
#62788
A
did refuse
B
needn’t have refused
C
couldn’t well refuse
D
did not say no
This cake is very sweet. You      a lot of sugar in it. 
#62688
A
should put
B
could have put
C
might put
D
must have put