I am not really sure where Nhung is. She.... in the living room, or perhaps she is in the backyard.
A.could not sit
B.cannot sit
C.must be sitting
D.might be sitting

John…. speak three languages.
A.will
B.can
C.has to
D.must

With luck, tomorrow.... be a sunny day.
A.could
B.must
C.would rather
D.needn't

Dane ....the book we borrowed from the library. It was on the table, but now it has gone.
A.must have returned
B.should have returned
C.cannot have returned
D.needn’t have returned

When I was five years old, I.... read and write.
A.can
B.could
C.may
D.should

It is hot in here. .... you open the window a bit, please?
A.Could
B.Must
C.Should
D.Might

The book is optional. My professor said we.... read it if we needed extra information for the essay. However, we.... read it if we don’t want to.
A.will / cannot
B.must / ought not
C.could / do not have to
D.can / should not

Please make sure to water my plants while I am gone. If they don’t get enough water, they.... die.
A.must
B.will
C.should
D.ought to

They.... be away for the weekend, but I am not sure.
A.needn’t
B.should not
C.must
D.might

You.... leave now if you wish.
A.have to
B.must
C.may
D.would