He was surprised ________ his best friend again.
| A．to see | B．seeing | C．see | D．sees |
He was just falling asleep________ there was a loud knock at the door.
| A．when | B．while | C．as | D．and |
Mary was dancing while Mike ________ the piano.
| A．played | B．was playing | C．were playing | D．plays |
The old man looked for the dog________
| A．anywhere | B．nowhere | C．somewhere | D．everywhere |
________ TV at that time?
| A．Did you watch | B．Have you watched |
| C．Were you watching | D．Are you watching |