It _____ me more than three days _____ I finished writing the paper.

A. cost, until 　 　B. took; before

C. spent; before 　 D. wasted; after

I can hardly remember any occasions _____ I get caught in a traffic jam in our town.

A. which　　　　　　 B. that 　　　　　 　 C. where　　　　 D. when

Electricity__________(discover)two thousand years ago.

It is well making the effort to learn how to do it.

A. known 　B. perfect　　 C. worth　　 D. proper

I won’t call you，　　　　 something unexpected happens.?

A.unless　　　 B.whether?　　 C.because　　　 D.while

When Polly came to, she found herself __________by a kind nurse in the hospital.

A. being taken care of　　　 B. looking after　　 C. taking care of　 D. taken care of

My cousin went to Canada two years ago.He　　　 there for a few months and then went to America.

A.worked　　 B.would work?　 C.would be working　　　 D.has been working

With the development of science and technology, more and more (農(nóng)業(yè))________

　 achievements have been make in China.