Câu hỏi: Some______ animals become tame if they get used to people.

A. wild

B. domestic

C. endangered

D. rare

Câu 1: The society was set up to______ endangered species from extinction.

A. prevent

B. distinguish

C. preserve

D. survive

Câu 2: The problem of_______ in big cities, which stems from uncontrolled migration from rural areas.

A. overpopulation

B. decrease

C. increase

D. growth

Câu 3: Intelligent ___________ are widely used in many fields such as heavy industries, hospital medicine business, and the military.

A. machines

B. service

C. advisement

D. computers

Câu 4: We kept in _______for a while after college.

A. touch

B. pay

C. well

D. chose

Câu 5: He had a new heart valve _______.

A. added

B. supplanted

C. improved

D. implanted

Câu 6: I_______ George on my way home.

A. dropped in on

B. gear up for

C. pair up with

D. look back on