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

A. melted

B. escaped

C. vanished 

D. perished

Câu 1: Adverse reviews in the New York press may greatly change the prospects of a new Broadway production.

A. subversive

B. additional

C. encouraging

D. unfavorable

Câu 2: Helen Keller, blind and deaf from an early age, developed her sense of smell so finely that she could identify friends by their personal odors.

A. classify

B. recognize

C. describe

D. communicate with

Câu 3: Studies of climatology indicate that volcanic dust in the atmosphere may contribute to the onset of ice ages.

A. explain

B. insinuate

C. suggest

D. prove

Câu 4: Scientists warn of the impending extinction of many species of plants and animals.

A. irrefutable

B. imminent

C. formidable

D. absolute

Câu 5: In the United States, a party can nominate a single candidate for office.

A. refuse

B. keep

C. change

D. appoint

Câu 6: 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