_______ about the universe up till now.
| A．So little had me known | B．Only a little do we know |
| C．Very little have we known | D．Little shall we know |
Mr. Smith, may I have a word with you? I’ll try not to __________ too much of your time．
| A．take up | B．take on | C．take in | D．take off |
You may catch up with others __________ you work a little harder.
| A．so long as | B．so far as | C．however | D．unless |
Without electricity human life __________ quite different today.
| A．is | B．will be | C．would have been | D．would be |
Gunpowder is generally believed __________ in ancient China.
| A．to have invented | B．being invented | C．to have been invented | D．having invented |
It was __________ great shock to the world that a French airplane got missing over __________ Atlantic Ocean on June 1st, 2009.
| A．a; ／ | B．the; the | C．a; the | D．/; the |