Câu hỏi: The 1908 Siberian meteorite explosion brought about considerable depletion of the northern hemisphere's ozone layer.

A. was caused by

B. resulted in

C. brought back

D. was initiated by

Câu 1: In the United States, a party can nominate a single candidate for office.

A. refuse

B. keep

C. change

D. appoint

Câu 2: The use of lasers in surgery has become relatively commonplace in recent years.

A. absolutely

B. relevantly

C. almost

D. comparatively

Câu 3: We watched as the plane disappeared behind the clouds.

A. melted

B. escaped

C. vanished 

D. perished

Câu 4: He was fired because of his misconduct at the office party.

A. mistake

B. impropriety

C. condition

D. singing

Câu 5: Scientists warn of the impending extinction of many species of plants and animals.

A. irrefutable

B. imminent

C. formidable

D. absolute

Câu 6: If petrol price go up any more, I shall have to use a bicycle.

A. develope

B. ascend

C. raise

D. increase