—The tickets to Texas are not available now．
—Oh．Flights ______ fast at festivals．
| A．sold | B．sell |
| C．will sell | D．have sold |
---Keep _____ in mind that you have to be home by 10 o’clock.
---Ok, I will.
| A．it | B．me | C．this | D．one |
We are at your service. Don’t to turn to us if you have any further problems.
| A．beg | B．hesitate | C．desire | D．seek |
A warm thought suddenly came to me __________ I might use the pocket money to buy some flowers for my mother’s birthday.
| A．if | B．when | C．that | D．which |
All living organisms (有机物), __________ their unique identity, have biological, chemical and physical characteristics in common.
| A．as a consequence of | B．for the sake of | C．in terms of | D．regardless of |
I have no idea when the bus will arrive. I for at least half an hour in such cold weather.
| A．had waited | B．have waited | C．will wait | D．have been waiting |