Câu hỏi: 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 1: 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 2: The mother asked her son if he would have the floor clean the day before.

A. asked

B. if

C. would have

D. clean

Câu 3: Do most boys and girls give a great deal of thought to their future employ?

A. most

B. give

C. thought

D. employ

Câu 4: Spell correctly is easy with the aid of a number of word processing programs for personal computers.

A. Spell

B. correctly

C. word processing

D. computers

Câu 5: Slowly and with care, the museum director removed the Ming vase from the shelf and placed it on the display pedestal.

A. with care

B. from

C. placed

D. the display pedestal

Câu 6: Narcissus, a character in mythology, gazed at his own image in a pool so ardently that he fell into itself and downed.

A. a character in mythology

B. his own

C. that

D. into itself