One of the consequences of our planet's being warming up is a（n）_______ in the number of natural disasters.
| A．result | B．account | C．reason | D．increase |
—You see，I’m poor in maths，you are not good at English，and...
—That’s________we should help each other.
| A．when | B．where | C．how | D．what |
______I am concerned，the price of the computer is much too high，so I can’t afford it.
| A．As long as | B．As far as | C．As well as | D．As often as |
Teachers recommend parents_____their children under 12 to ride bicycles to school for safety.
| A．not allow | B．do not allow |
| C．mustn’t allow | D．couldn’t allow |
The following are some popular websites________people can sell goods to each other.
| A．where | B．which | C．when | D．whose |
______ by a snake, she was frightened of it.
| A．Being bitten | B．To bite | C．Having been bitten | D．Biting |