—I really don't know what I ________yesterday without the bike you lent me.
—Glad to have been some help to you.
| A．could do | B．should have done |
| C．had done | D．could have done |
---It was dangerous to throw that bottle out of the window. You could have hurt someone.
---I’m so sorry! I _______ .
| A．am not thinking | B．wasn’t thinking | C．haven’t thought | D．don’t think |
Tsinghua University, ______ in 1911, is home to a great number of outstanding figures.
| A．found | B．founding | C．founded | D．to be founded |
---May I take this book out of the reading room?
---No, you______. You read it in here.
| A．mightn’t | B．won’t | C．needn’t | D．mustn’t |
---We could invite John and Barbara to the Friday night party.
---Yes, _______? I’ll give them a call right now.
| A．why not | B．what for | C．why | D．what |
If you forget ______ your watch, it is likely to stop soon.
| A．to wind up | B．to wind off | C．winding up | D．winding off |