He never thought of it before, ________all that his parents had done for him for granted.
| A．taking | B．taken | C．to take | D．took |
I must go now. _____, if you want that book I'll bring it next time.
| A．Incidentally | B．Accidentally |
| C．Occasionally | D．Subsequently |
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 |
With sufficient scientific information a manned trip to Mars should be _____.
| A．obtainable | B．potential | C．considerable | D．feasible |