As nobody here knows what is wrong with the machine, we must send for an engineer to ______ the problem.
| A．handle | B．raise | C．face | D．present |
the new underground is available has not been made clear yet.
| A．When | B．How | C．What | D．That |
It's a common _______ for young people to pay a New Year's visit to their elders.
| A．sense | B．practice | C．rule | D．scene |
—Would you mind giving your advice on how to improve our business management?
—If you make ____ most of the modern equipment, there will be ____ rise in production．
| A．不填; 不填 | B．the; a | C．不填; a | D．the; 不填 |
---Have all the mysteries been cleared up?
--- Almost. But ______ only one question ______.
| A．there remains; answered | B．it remains; to be answered |
| C．there remains; to be answered | D．it remains; answered |
I will never forget my stay there I found my lost wallet.
| A．which | B．that | C．where | D．when |