In the last few years,China ___ great achievements in environmental protection.

A. has made B. had made

C. was making D. is making

—Is Peter coming?

—No, he____ his mind after a phone call at the last minute.

A. changes B. changed

C. was changing D. had changed

Albert Einstein was born in 1879. As a child, few people guessed that he a famous scientist whose theories would change the world.

A. has been B. had been

C. was going to be D. was

--Did you enjoy the party?

--Yes, we___by our hosts.

A. were treated B. would be treated.

C. treated D. had treated

I had a strong desire to reach in and play with the toy, but ________ thankfully by the shop window.

A. am held back B. held back

C． hold back D． was held back

—Did you have difficulty finding Ann' house?

—Not really.She___us clear directions and we were able to find it.easily?

A. was to give B. had given

C. was giving D. would give

—Dr. Jackson is not in his office at the moment.

—All right. I____ him later.

A. will call B. have called

C. call D. will be calling

That's why I help brighten people's days. If you ________， who's to say that another person will?

A. didn't B. don't

C．weren't D． haven't

In my hometown, there is always a harvest supper for the farmers after all the wheat____ cut.

A. will have been B. will be

C. was D. has been

As you go through this book, you ________ that each of the millions of people who lived through World War II had a different experience.

A. will find B. found

C. had found D. have found