Many people agree that ______ knowledge of English is a must in _______ international trade today.
| A．the, an | B．a, 不填 | C．the, the | D．不填, the |
We live too far from the city to get a strong TV ________.
| A．sign | B．symbol | C．mark | D．signal |
It was last Saturday ________ we visited the History Museum.
| A．which | B．and | C．where | D．that |
I suggested that the problem _____as soon as possible.
| A．referred to being solved | B．referred be solved |
| C．referred to be solved | D．referred should be solved |
When ________ to the market, these products were very popular.
| A．introducing | B．introduced |
| C．introduce | D．being introduced |
His English, ______ used to be very poor is now excellent.
| A．which | B．that | C．it | D．whom |