小伙伴给你看他的新文具,你会说:
What ___ they playing ? A. are B. am C. is
What are they ____? A.matter. B. doing. C. look.
She is ____. A. this B. what. C.talking.
We ___ a happy family. A. a B. is C.are
My mother ___ a doctor . A.am B. is C. are