A new teachnique ____the yields as a whole increased by about 30 percent.
| A．had applied | B．having applied | C．to have applied | D．having been applied |
Scientists think they have _____ in their attempt to find the causes of some major dieases.
| A．broken through | B．worked out |
| C．fallen out | D．got round |
. If you ever have the _____ to go abroad to work, you should take it.
| A．possibility | B．offer | C．luck | D．chance |
I'd like to take _____ of this opportunity to thank you all for your cooperation.
| A．profit | B．benefit | C．advantage | D．interests |
I could tell he was surprised from the _____ on his face.
| A．appearance | B．view | C．sight | D．expression |
We had a marvelous holiday: only the last two days were slightly _____ by the weather.
| A．damaged | B．hurt | C．ruined | D．spoiled |