Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

Câu hỏi

_______ in open fires, rubbish and organic waste produce a great amount of black carbon.

A. Burnt

B. Burning

C. Be burnt

D. To burn

Đáp án
A. Burnt

Câu hỏi thuộc Bài tập:

E11- GS- Test for Unit 6 (2)