Câu hỏi: For thousands of years, man has created sweet-smelling substances from wood, herbs and flowers and using them for perfumes or medicine.

A. man

B. sweet-smelling

C. using them

D. or

Câu 1: Sometimes it takes me about three hours finishing my round.

A. sometimes

B. me

C. hours

D. finishing

Câu 2: Although caffeine is a moderately habit-forming drug, coffee is not regarded as harmfully to the average healthy adult.

A. moderately

B. habit-forming

C. harmfully

D. healthy

Câu 3: Unlike the old one, this new copier can perform their functions in half the time.

A. unlike

B. can perform

C. their functions

D. in half the time

Câu 4: Little have people done to alleviate the sea pollution caused by the factories in central Vietnam, haven’t they?

A. have people done

B. caused

C. in central

D. haven’t they

Câu 5: Manufacturers may use food additives for preserving, to color, or to flavor, or to fortify foods.

A. may use

B. for preserving

C. to flavor

D. to fortify

Câu 6: Building thousands of years ago, the ancient palace is popular with modern tourists.

A. building

B. ago

C. the ancient 

D. popular with