They always lay a large supply of tinned food in winter in case they are snowed up.
| A．out | B．off | C．in | D．with |
No matter how bright a talker you are, there are times when it's better ________ silent.
| A．remain | B．be remaining |
| C．having remained | D．to remain |
________basic firstaid techniques will help you respond quickly to emergencies.
| A．Known | B．Having known |
| C．Knowing | D．Being known |
If he takes on this work, he will have no choice but ________ an even greater challenge.
| A．meets | B．meeting |
| C．meet | D．to meet |
Shortly after suffering from a massive earthquake and ________ to ruins, the city took on a new look.
| A．reducing | B．reduced |
| C．being reduced | D．having reduced |
The ability ________ an idea is as important as the idea itself.
| A．expressing | B．expressed |
| C．to express | D．to be expressed |