1. “Someone is knocking at the door. ___________________it be Mary?”
   -“It ___________________Mary. To my certain knowledge she is in Moscow.”
   A. May/isn’t B. Might/may not be  C. Could/can’t be   D. Is/can’t be
2. Travel broadens the mind. Therefore, I _________________to over five countries for two months now.
   A. have traveled B. travel                     C. am traveling         D. have been traveling

3. The wind was so strong that it ____________________his tent to pieces.
   A. broke                 B. tore            C. smashed                D. destroyed

4. I hate _______________when my friends use my computer without asking permission.
   A. that                     B. a thing                   C. about                     D. it