He stood up and ________ a smile to cover up his disappointment.
| A．hid | B．managed |
| C．refused | D．brought |
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 |
Carl wanted to play a joke on Bob but gave himself _____ by laughing.
| A．away | B．in | C．out | D．up |
As he had no friends and relatives in the town, the traveler tried to find a _____ somewhere.
| A．log | B．lodge | C．landing | D．lodging |
The thieves _____ him _____ in the park, took his wallet and escaped.
| A．held .. back | B．held .. up | C．held .. on | D．held .. out |