-- Is it your brother playing football outside? -- It ________ be him. He is helping mother with dishes now.
#76128
A
must
B
can’t
C
mustn’t
D
can
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— Happy birthday!— Thank you! It’s the best present I _______ for.
#63508
A
should have wished
B
must have wished
C
may have wished
D
could have wished
The door _______ open, no matter how hard she pushed. 
#62534
A
shouldn‘t
B
couldn't
C
wouldn't
D
mightn't