Here is so difficult a problem_______none of us can solve.
| A．which |
| B．that |
| C．as |
| D．what |
The ability ________ an idea is as important as the idea itself.
| A．expressing | B．expressed |
| C．to express | D．to be expressed |
Volunteering gives you a chance ________ lives, including your own.
| A．change | B．changing |
| C．changed | D．to change |
Tom asked the candy makers if they could make the chocolate easier ______ into small pieces.
| A．break | B．breaking |
| C．broken | D．to break |
This machine is very easy ________. Anybody can learn to use it in a few minutes.
| A．operating | B．to be operating |
| C．operated | D．to operate |
______an important role in a new movie, Andy has got a chance to become famous.
| A．Offer | B．Offering |
| C．Offered | D．To offer |