Câu hỏi: Hypertension is one of the most widespread and potential dangerous diseases.

A. colossal

B. popular

C. common

D. scattered

Câu 1: We watched as the plane disappeared behind the clouds.

A. melted

B. escaped

C. vanished 

D. perished

Câu 2: He was fired because of his misconduct at the office party.

A. mistake

B. impropriety

C. condition

D. singing

Câu 3: The raccoon is a nocturnal animal.

A. harmless

B. night

C. marsupial

D. diurnal

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: 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 6: He was asked to account for his presence at the scene of crime.

A. complain

B. exchange

C. explain

D. arrange