______I understand your viewpoint, I don’t agree with it.
| A．Unless | B．Since | C．Before | D．While |
Before the tourists set off, they spent much time setting a limit __________ the expenses of the trip.
| A．in |
| B．for |
| C．to |
| D．about |
There is a limit __________ people's life, but no limit __________ the knowledge.
| A．on; to learn |
| B．to; to learn |
| C．on; learning |
| D．to; to learning |
Unfortunately, the research was limited __________ increasing economic profits，__________ protecting the environment.
| A．to; other than |
| B．by; rather than |
| C．to; rather than |
| D．by; more than |
They are trying to find a new way to __________ the spread of AIDS.
| A．keep |
| B．delay |
| C．catch |
| D．arrest |
They will have you __________ if you don't pay taxes, because it is everyone's duty to pay taxes.
| A．arrest |
| B．arrested |
| C．to be arrested |
| D．being arrested |