I regret _____ hard at school, or I would have succeeded in passing the exam.
| A．not to work |
| B．having not worked |
| C．to have not worked |
| D．not having worked |
Something will have to be done about the air pollution, _______ ?
| A．does it |
| B．won't it |
| C．has it |
| D．will it |
Everyone's having a good time,_______?
| A．aren't they |
| B．does he |
| C．is he |
| D．isn't everyone |
We forgot to bring our tickets, but please let us enter,_______?
| A．do you |
| B．can we |
| C．will you |
| D．shall we |
You had better clear up your bedroom,_______?
| A．didn't you |
| B．hadn't you |
| C．did you |
| D．had better you |
We need to repair the house before it rains, _______?
| A．needn't we |
| B．needn't you |
| C．don't you |
| D．don't we |