--- _____ they taking a picture?
--- Yes, they are.
A. AmB. IsC. Are
Kate ______ playing chess.
A. am B. is C. are
______ season do you like best?
A. WhichB. WhatC. How
What do you do ______ the weekend?
A. onB. inC. at
---Is there a mirror in the house? ---___________.
A. Yes, there is B. Yes, it isC. Yes, there are