- How long did David work here?
- For half a year, he didn't leave much_______on us.
| A．expression | B．instruction |
| C．conclusion | D．impression |
It is wise of you towell trained workers for untrained ones in your workshop.
| A．substitute | B．change | C．exchange | D．employ |
Many students listened to the lecture, but I wondered how much they.
| A．took out | B．took up | C．took off | D．took in |
The customs office isyour luggage is inspected when you enter or leave a country.
| A．where | B．when | C．why | D．who |
We are proud of our hometown, which isin coal and natural crystal（水晶石）.
| A．abundant | B．universal | C．remote | D．autonomous |
However much you have done, you ought tothe help you’ve received from others.
| A．donate | B．acknowledge | C．conduct | D．guarantee |