— I missed the earliest flight in the morning. It was really a pity.
—You _________ to the airport by taxi instead of by bus.
| A．should go | B．should have left | C．should leave | D．must have gone |
32．Many experiments_____before the research team was able to get the exact data to carry on project.
| A．have done | B．had been doing | C．had been done | D．have been done |
31．Either you or on of your students________to attend the meeting that is due tomorrow.
| A．are | B．is | C．have | D．Be |
30．When he came back, he found the bag he had________over the seat was gone.
| A．left to hang | B．left hanging | C．to leave hung | D．to leave hanging |
29．What has been studied suggest that a short nap in the afternoon_______you refreshed for the next four or five hours.
| A．will leave | B．leaves | C．must leave | D．should leave |
28．—How about setting up an out-of-class club to share our interests and hobbies?
—Great! That’s exactly what I_________.
| A．was thinking | B．think | C．had thought | D．will think |