_____, he always tries his best to complete it on time.
| A．However the task is hard | B．However hard the task is |
| C．Though hard the task is | D．Though hard is the task |
You all had a good time yesterday,________?
| A．hadn’t you | B．haven’t you | C．didn’t you | D．don’t you |
The Greens seldom go to the concert,________?
| A．don’t they | B．do they | C．don’t he | D．do he |
The shop doesn’t open until 11 a. m.,________ it loses a lot of business.
| A．for | B．or | C．but | D．so |
Most of the Europeans refuse to accept GM food________Americans regard it as the fruit from high tech.
| A．when | B．as | C．while | D．the moment |
Rod is determined to get a seat for the concert________it means standing in a queue all night.
| A．so that | B．however | C．even though | D．as if |