At the Copenhagen conference, all the countries were called on to do all they could to control greenhouse gas emissions ______ it was too late.
| A．when | B．after | C．until | D．before |
When a pencil is partly in a glass of water, it looks as if it ______.
| A．breaks | B．has broken |
| C．were broken | D．had been broken |
. You didn’t let me drive. If we ____ in turn, you ____ so tired.
| A．drove; didn’t get | B．drove; wouldn’t get |
| C．were driving; wouldn’t get | D．had driven; wouldn’t have got |
Yesterday, Jane walked away from the discussion. Otherwise, she ____ something she would regret later.
| A．had said | B．said |
| C．might say | D．might have said |
If only he _______ quietly as the doctor instructed, he would not suffer so much now.
| A．lies | B．lay |
| C．had lain | D．should lie |
It is hard for me to imagine what I would be doing today if I ____ in love, at the age of seven, with the Melinda Cox Library in my hometown.
| A．wouldn’t have fallen | B．had not fallen |
| C．should fall | D．were to fall |