----- Nội dung dịch tự động từ ảnh ----- 15. Thousands of people jammed into People's Square to watch fireworks..... A. performance B. display C. demonstration 16. .....is a continuous supply of the basic necessities of life. A. What is needed B. For our needs C. The things needed 17. It's essential that every student.....the exam before attending the course. A. pass B. passes C. passed 18. .....be needed, the water basin will need to be dammed. A. When hydroelectric power B. Hydroelectric power C. Should hydroelectric power 19. She is going to take extra lessons to.....what she missed while she was away. A. catch up with B. cut down on C. put up with 20. .....in the atmosphere is the temperature falling below the freezing point. A. Frost is produced B. Frost produces C. What produces frost D. entertainment D. That is needed D. would pass D. Hydroelectric power should D. look down on D. What is frost produced