Câu hỏi: Conservation is the safeguarding and preservation of nature resources.

A. is

B. safeguarding

C. preservation

D. nature

Câu 1: Ecologists are trying to preserve our environment for future generations by protecting the ozone layer, purifying the air, and have planted the trees that have been cut down.

A. to preserve

B. for

C. the ozone layer

D. have planted

Câu 2: What happened in New York were a reaction from city workers, including firemen and policemen who had been laid off from their jobs.

A. What happened

B. were

C. including

D. their

Câu 3: Teddy Roosevelt demonstrated his competitive spirit and tireless energy in 1905 whenever he led the Rough Riders up San Juan Hill.

A. demonstrated

B. competitive

C. whenever

D. he

Câu 4: Robots in the home might not be enough creative to do the cooking, plan the meal and so on.

A. in the home

B. might

C. enough creative

D. do the cooking

Câu 5: Do most boys and girls give a great deal of thought to their future employ?

A. most

B. give

C. thought

D. employ

Câu 6: The mother asked her son if he would have the floor clean the day before.

A. asked

B. if

C. would have

D. clean