( )—Is the cat ________ the door? —No, it isn’t. It’s ________.
()They _____going to different schools. A. is B. are C. do
()I _____the name of a friend. A. write B. writing C. am write
()There is _____ big bird in the tree. A. a B. an C. the
()Why are you _____ ? A. laugh B. laughing C. sing
()Why do you _____cups on your heads? A. have B. having C. had