—______I use your computer to send an e-mail?
—Yes, you ______. But you mustn’t keep it too long.I’ll surf the Internet after supper.
| A．Could; could | B．Could; must | C．Can; can | D．Could; can |
Achieving a high degree of proficiency in English as a foreign language is not a mysterious _____ without scientific basis.
| A．process | B．practice | C．procedure | D．program |
They were so far away that I couldn't _____ their faces clearly.
| A．see through | B．make up | C．see off | D．make out |
If the boy had _____ the dog alone it wouldn't have bitten him.
| A．set | B．left | C．had | D．put |
The generation _____ makes it difficult for parents to understand their children's opinions.
| A．division | B．gap | C．separation | D．interval |
With sufficient scientific information a manned trip to Mars should be _____.
| A．obtainable | B．potential | C．considerable | D．feasible |