We had just covered half the journey________the engine failed and we could do nothing but wait for help.
| A．before | B．since |
| C．when | D．until |
John is a lazy student,one of_________ bad study habits is to leave for tomorrow_____ ought to be done today.
| A．his;something | B．whose;what |
| C．whom;that | D．his;that |
A new technique_________, the yields as a whole increased by 20 percent.
| A．working out |
| B．having worked out |
| C．having been worked out |
| D．to have been worked out |
Take this medicine,_________ you will be getting worse.
| A．or rather | B．or else |
| C．for that | D．for another |
The boy was seen_________ in the examination and was punished by the teacher.
| A．having cheated | B．cheated |
| C．cheating | D．cheat |
Switzerland refused to_________ the two world wars.
| A．take part | B．take sides in |
| C．join | D．attend |