I know it’s normal for such a thing to happen，but we________it if we’d been more careful.
| A．need have avoided | B．could have avoided |
| C．will have avoided | D．had avoided |
—Another cup of coffee? That’s your third since lunch.
—Yeah, well, I ____ all night preparing for my history exam. I can hardly keep my eyes open.
| A．stayed up | B．have stayed up | C．have been staying up | D．will stay up |
—What’s up? You look down. —I have piles of papers ________, but I type so slowly.
| A．to be typed | B．typed | C．to type | D．being typed |
We must apply what we have learned to our daily work because in no case _____ from practice.
| A．should theory separate | B．should theory be separated |
| C．theory should separate | D．theory should be separated |
—Why do you look so worried?
—My computer broke down and my essay ______ unfinished since.
| A．was left | B．has left | C．left | D．has been left |
Nowadays teachers tend to be more dependent on ________ is thought to be a great teaching aid—the computer.
| A．that | B．which | C．what | D．as |