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

A. measuring

B. the

C. how

D. is it

Câu 1: She only had a twenty-dollars bill with her when she landed at Healthrow airport.

A. had

B. twenty-dollars bill

C. when

D. at

Câu 2: Building thousands of years ago, the ancient palace is popular with modern tourists.

A. building

B. ago

C. the ancient 

D. popular with

Câu 3: 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 4: It is believed that in the near future robots will be used to doing things such as cooking.

A. it is believed

B. in the near future

C. be used to cooking

D. such as

Câu 5: Not everyone realizes that the most largest organ of the human body is the skin.

A. not everyone

B. most largest

C. human

D. is

Câu 6: I enjoy reading the article that you told me about it yesterday.

A. reading

B. that

C. told

D. it