We all know that we ________ our carbon footprint, but I suspect that many people wouldn't be prepared to go as far as Joan Pick, a retired scientist living in south London.
| A．must have reduced | B．should have reduced |
| C．may have reduced | D．could have reduced |
—If you like the new computer, I suggest buying it.
—But it's really too expensive. I can't __________ it.
| A．get |
| B．afford |
| C．provide |
| D．support |
The Sun's activity has a strong __________ on the Earth.
| A．reputation |
| B．influence |
| C．impression |
| D．knowledge |
The manager is said to have arrived back from Paris where he __________ some European business partners.
| A．would meet |
| B．is meeting |
| C．meets |
| D．had met |
When he found many people were gathering there, he went to see what __________.
| A．happened |
| B．would happen |
| C．has happened |
| D．had happened |
He __________ that until he __________ the directions once again.
| A．didn't understand ； had read |
| B．hadn't understood ； read |
| C．understood ；had read |
| D．understood ； read |