Câu hỏi: People are destroying the air by adding ...... to it.

A. pollutants

B. polluters

C. pollution

D. polluted

Câu 1: The leopard is _________ the threat of extinction.

A. in

B. on

C. under

D. below

Câu 2: It is possible for local wildlife to coexist ...... industry.

A. to

B. of

C. in

D. with

Câu 3: A hydroelectric dam ______________ in this area now.

A. is building

B. is being built

C. build

D. was built

Câu 4: The ...... friendly products are designed not to harm the natural environment.

A. environment

B. environmental

C. environmentally

D. environmentalism

Câu 5: The boy found a wallet in the street, and then he ...... to return it to the loser.

A. tried

B. had tried

C. was trying

D. had been trying

Câu 6: The panda's ...... habitat is the bamboo forest.

A. nature

B. natural

C. naturalized

D. naturally