____ a strong and fair climate agreement at the key UN summit in Copenhagen, 50,000 people in London wore blue and went to the streets．
| A．Call for | B．Calling for | C．To call for | D．Called for |
To the foreigners, the Great Wall is worth ______.
| A．pay a visit | B．paying a visit |
| C．paying a visit to | D．being paid a visit to |
It ___ we had stay together for a couple of weeks ___ I found we had a lot in common.
A.was until; whenB was until; that
C. wasn’t until; when D. wasn’t until; that
No one can walk the wire in the air without a bit of fear unless ___ very young.
| A．having trained | B．trained |
| C．to be trained | D．being trained |
Neither the old lady nor her cats ___ out of the house since her husband passed away last month.
| A．was stepping | B．have stepped |
| C．stepped | D．has stepped |
After supper, he usually stood near the window, ___ he could see the tower, the tallest building of the town.
| A．from which | B．from where |
| C．on which | D．on where |