There is no simple answer，__________ is often the case in science.
| A．as | B．that |
| C．when | D．where |
33．—There will be a talk show this time tomorrow．Would you go with me?
—I'm sorry, but I ______ an important meeting．
| A．have attended | B．will be attending |
| C．am about to attend | D．would attend |
32．She shouldn't be working so hard —She is 70, ___ .
| A．in any case | B．above all |
| C．in a way | D．after all |
31．_____Tom has no interest in piano, there is no point pushing him to learn it．
| A．Now that | B．In case | C．Even if | D．As if |
30．—Peter looked tired and a little absent-minded at the meeting．
—He _____ up too late．
| A．may stay | B．could stay |
| C．should have stayed | D．must have stayed |
29．His humorous closing speech was a welcome addition to the ______dull meeting．
| A．therefore | B．meanwhile | C．otherwise | D．Thus |