Some of the people often ask the same question the air has been polluted.
| A．whether | B．if | C．that | D．where |
It was on a cold winter evening_______ his father left home and was never back.
| A．where | B．which | C．that | D．when |
Whoever leaves the room last must ______ that all the lights are turned off.
| A．is sure | B．make sure | C．find out | D．look out |
---- _____? ---- You were saying you sold the house and left your hometown.
| A．How come | B．Like what? |
| C．Do you have the time | D．Where was I |
Suddenly, the lightning flashed through the clouds, nearly ____ Paul.
| A．beating | B．blinding | C．burning | D．touching |
Keep up good state of mind even if you _____ fail plenty of times.
| A．must | B．will | C．can | D．should |