They___friends since they met in Shanghai
| A．have made |
| B．have become |
| C．have been |
| D．have turned |
David caught a bad cold last Tuesday. Luckily, the cold didn't ______ his examination in physics.
| A．decrease |
| B．spread |
| C．affect |
| D．protect |
-What are you worried about?
-Tom didn't respond ______ any of my e-mails. Something must have happened to him.
| A．on |
| B．with |
| C．for |
| D．to |
It is almost ______ that every organization has too many meetings, most of which are poorly prepared.
| A．expected |
| B．certain |
| C．secure |
| D．powerful |
-Can I smoke here?
-Sorry. We don't allow ______ here.
| A．people smoking |
| B．people smoke |
| C．to smoke |
| D．smoking |
Once harm is ______ to the eco-system, all species will ______ , including man himself .
| A．made; be in danger |
| B．done; be dangerous |
| C．caused; be endangered |
| D．done; be in danger |