Câu hỏi: I would like to send these letters …………………..air mail.

A. in

B. with

C. by

D. over

Câu 1: A hydroelectric dam ______________ in this area now.

A. is building

B. is being built

C. build

D. was built

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

A. to

B. of

C. in

D. with

Câu 3: Could you please provide us ……………..some more modern equipment?

A. for

B. by

C. in

D. with

Câu 4: The panda's ...... habitat is the bamboo forest.

A. nature

B. natural

C. naturalized

D. naturally

Câu 5: The waste from the chemical factory is extremely .......

A. harm

B. harmful

C. unharmed

D. harmless

Câu 6: The ...... friendly products are designed not to harm the natural environment.

A. environment

B. environmental

C. environmentally

D. environmentalism