Câu hỏi: 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 1: There are many different ways of comparing the culture of one nation with those of another.

A. There are

B. of comparing

C. those

D. another

Câu 2: By measuring the color of a star, astronomers can tell how hot is it.

A. measuring

B. the

C. how

D. is it

Câu 3: 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 4: I clearly remember to tell you about this before.

A. clearly

B. remember

C. to tell 

D. about

Câu 5: 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 6: Sometimes it takes me about three hours finishing my round.

A. sometimes

B. me

C. hours

D. finishing