During the next ten years we both worked day and night to
_____ the money we had borrowed.
| A．pay off | B．pay for | C．pay to | D．pay back |
We_______on this project for four hours. Let’s have a rest.
| A．are working | B．have been working | C．worked | D．had worked |
Many people believe we are heading for environmental disaster _____ we basically change the way we live.
| A．but | B．although | C．unless | D．once |
She longed for a pleasant trip in the summer, while her parents desired that she_______ at home, preparing for the coming exam..
| A．stay | B．stays | C．must stay | D．would stay |
Jack has made great achievements in his work, and the harder he works, the more _________ he becomes.
| A．religious | B．energetic | C．curious | D．independent |
This depends uponhe is interested in doing this kind of work.
| A．if | B．whether | C．that | D．what |