Some people argue using _____ nature to meet our own needs may spell disaster, unless we start to look around and understand how ______ clean environment benefits us all.
| A．/; a | B．the; the | C．the; a | D．a; a |
- I'm going to San Francisco for a couple of days.
-I wish I could get away for a while.
| A． | It doesn't matter | B． | Forget it |
| C． | I really envy you | D． | I can't agree more |
Had they known what was coming next, theysecond thoughts.
| A． | may have | B． | could have | C． | must have had | D． | might have had |
Mike was usually so careful, ______this time he made a small mistake.
| A．yet | B．still | C．even | D．thus |
Ellen was a painter of birds and of nature, _____, for some reason, had withdrawn from all human society.
| A．which | B．who | C．where | D．whom |
- Alvin, are you coming with us?
- I'd love to, but something unexpected.
| A． | has come up | B． | was coming up | C． | had come up | D． | would come up |