He made another wonderful discovery, ______ of great importance to science.
| A．which I think is | B．which I think it is |
| C．which I think | D．I think which is |
Teachers should create an environment children are taught how to solve problems of learning by themselves.
| A．why | B．where | C．which | D．whose |
The car crashed into the back of a truck and the driver was trapped for about an
hourbeing taken to hospital.
| A．when | B．before | C．after | D．until |
that ,or one day you may come to be ashamed of what you have done.
| A．Stop doing | B．If you stop doing |
| C．If you don’t stop doing | D．You stop doing |
An idea occurred to her she might work out the maths problem in another way.
| A．who | B．why | C．that | D．what |
At present, business is not good in these skiing resorts, but I’m sure things will start
to in winter.
| A．rise up | B．hang up | C．take up | D．pick up |