_________ the window, my finger was seriously cut.
A. Having cleaned B, To clean
C, While cleaning D. While I was cleaning
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 |
Mr Black is the professor_________I have the greatest respect.
| A．to whom | B．for whom |
| C．whom | D．who |