Câu hỏi: ……………fax transmission is commonly used in most offices.

A. A

B. An

C. The

D. x

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

A. is building

B. is being built

C. build

D. was built

Câu 2: I threw my old trainers and bought some new .................. .

A. ones

B. one

C. some

D. any

Câu 3: Laura reminded her roommate ...... her alarm clock for 6:00.

A. to set

B. setting

C. to be set

D. of setting

Câu 4: People are destroying the air by adding ...... to it.

A. pollutants

B. polluters

C. pollution

D. polluted

Câu 5: I would like to send these letters …………………..air mail.

A. in

B. with

C. by

D. over

Câu 6: The leopard is _________ the threat of extinction.

A. in

B. on

C. under

D. below