Much time _____ sitting at a desk, office workers are generally troubled by health problems.
| A．being spent | B．having spent |
| C．spent | D．spending |
If the Watergate Incident__________Nixon would not have resigned from the presidency.
| A．did not occur | B．had not occurred |
| C．was not occurring | D．be circling |
The sun rises in the east and sets in the west，so it seems as if the sun__________round the earth.
| A．were circling | B．circles |
| C．is circling | D．be circling |
If you hadn’t taken such a long time to get dressed，we’d __________there by now.
| A．be | B．circles | C．is circling | D．be circling |
I apologize if I__________you，but I assure you it was unintentional(无意的).
| A．offend | B．had offended |
| C．should have offended | D．might have offended |
I would have gone to visit him in the hospital，had it been at all possible，but I __________fully occupied the whole of last week.
| A．were | B．had been | C．have been | D．was |