—The terrible accident is under investigation.
—Actually, quicker action ______ those workers trapped in the mine.
| A．might have saved | B．must have saved | C．should have saved | D．could have saved |
The American girlfather is an engineer is my pen friend．
| A．who | B．whose | C．that | D．which |
Is some German friends visited last week ?
| A．this school where | B．this the school where |
| C．this the school | D．this school |
Winter is the time of the yearthe days are short and nights are long．
| A．on which | B．that | C．when | D．where |
--- What ______ when I phoned you?
--- I ______ my work, and I was about to go out．
| A．have you done; finished | B．were you doing; have finished |
| C．did you do; had just finished | D．were you doing; had just finished |
It was the first time ________ I ________ face to face with a thunder storm.
| A．when / had come | B．that / have come | C．when / came | D．that / had come |