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Li Yuanshen and I ________ good friends.
A．be B．is C． am D．are
There 50 students in our class.
A．be
B．is
C．am
D．are
_____your sister sad?
A．Are
B．Is
C．Am
D．Be
Maths ________ my favourite subject.
[ ]
A
B
C
D
How ______you?
A．am B．is C．are D．be