Câu hỏi: We all regard pollution as a.......... matter to human beings.

A. solemn 

B. great

C. serious 

D. huge

Câu 1: He had a new heart valve _______.

A. added

B. supplanted

C. improved

D. implanted

Câu 2: This_______disease caused a lot of complications during the treatment procedure.

A. situation

B. difficult

C. life-threatening

D. weak

Câu 3: _______ does not exist yet, but scientists are working hard to create computers that can think like human beings.

A. Advancement

B. Destruction

C. Intervention

D. Artificial intelligence

Câu 4: Installing is firewall is one method of trying to protect against_______.

A. hackers

B. thiefs

C. robbers

D. crooks

Câu 5: The waste water from bath, showers, sinks and_______, and rainwater can be collected in a tank.

A. linguistic

B. official

C. dishwasher

D. operate

Câu 6: The_______ of living here, of course, is that it is expensive.

A. glorious

B. athletic

C. strategy

D. downside