The exhibition tells us we should do something to stop air pollution.
| A．where | B．why | C．what | D．which |
She has been working hard day and night, which of course, _______ her pale face.
| A．accounts for | B．stands for |
| C．goes for | D．answers for |
--- Are you satisfied with what he did?
--- No. It couldn’t have been ______.
| A．worse | B．better | C．so bad | D．the worst |
--- He worked out such different questions at a very young age.
--- Oh, he ______ a very smart student then.
| A．could have been | B．should have been |
| C．might have been | D．must have been |
In our childhood, we were often ______ by Grandma to pay attention to our table manners.
| A．demanded | B．reminded | C．allowed | D．hoped |
Many lifestyle patterns do such _____ great harm to health that they actually speed up ____ weakening of the human body.
| A．a; 不填 | B．不填; the |
| C．a; the | D．不填；不填 |