Is the man over there Adam?
It ____ be him. He has gone to Hong Kong on vacation. ( )
A.mustB.can'tC.mustn't
These great books _______ by people all over the world today.( )
were read
read
are read
The doctor wanted to know _______ this morning.( )
what did you have
what you had
what you have
The zebra eats grass,but it ________ eat meat.( )
doesn't
didn't
don't
Look!Some old people _______ in the park.( )
sings
sing
are singing
Guilin isn't as _______ as Beijing.( )
big
bigger
biggest