___you may have,you should gather your courage to face the challenge
| A．However a serious problem |
| B．What a serious problem |
| C．However serious a problem |
| D．What serious a problem |
It snowed heavily for three days ____ and they were separated from the outside world.
| A．in the end | B．on end | C．by the end | D．at the end |
______everyone can hear the speaker there is no____ of turning up the radio.
| A．Now that; point | B．Even if; point | C．Now that; need | D．Even if; need |
If it was not an accident, he must have done it _____ .
| A．on purpose | B．in common | C．on occasion | D．in time |
Many students signed up for the ____ race in the sports meeting to be held next week.
| A．800-metre-long | B．800-metres-long | C．800 metre length | D．800 metres length |
____ Knowledge of English is a must in international trade.
| A．the | B．/ | C．A | D．An |