Many countries are now setting up national parks ________ animals and plants can be protected.

A. when B. which

C. whose D. where

We have launched another man－made satellite，________ is announced in today's newspaper.

A. that B. which

C．who D．what

The children, ______ had played the whole day long, were worn out.

A. all of what B. all of which

C. all of them D. all of whom

It was Mr. Zhang that helped us out of the trouble. Without his help, we ______ it so easily.

A. can’t manage B. mustn’t have managed

C. couldn’t have managed D. couldn’t manage

— It’s no easy task to catch a ticket on a website that receives 1 billion clicks daily.

—I can’t agree with you more. There ________ be errors for every single step.

A．should B．must

C．will D．can

—What a pity! Their experiment is a failure.

—They ________ better under more favorable conditions.

A. should have done B. could have done

C. must have done D. may have done

________ anyone come to my office, please tell them I'm not available before four o’clock.

A. Might B. Could

C. Would D. Should

— Joe, don’t forget to bring your laptop with you tomorrow, OK?

— Oh, thank you. I wouldn’t bring it if you _____ me.

A. wouldn’t remind B. haven’t reminded

C. hadn’t reminded D. shouldn’t have reminded

What if you _____ to send an essay with your application? Would you have been rejected?

A. forget B. would forget

C. had forgotten D. should forget

We got in my father's car and headed straight home and __________,I surely would have been stuck in the station for several days.

A. had I not B. did I not

C. if I didn't D. if I had