Grandpa was shocked by the news. Rarely ______ him so quiet.
| A．do I see |
| B．had I seen |
| C．I had seen |
| D．I saw |
Once ____ in the forest, you ought to remain ____ you are waiting for help．
| A．losing; where | B．losing; there | C．lost; there | D．lost; where |
You will succeed in the end ____ you give up halfway．
| A．even if | B．as though | C．as long as | D．unless |
____ made things worse, he said, was that his roommate never took part in any of the cleaning work．
| A．What | B．Which | C．That | D．Who |
Many things such as going abroad and owning a car, ____ impossible in the past, are now very common．
| A．being considered | B．to be considered |
| C．considering | D．considered |
Walking exercises ____ be boring at times, but on a clear sunny morning nothing could be better．
| A．may | B．will | C．must | D．should |