----- Nội dung dịch tự động từ ảnh ----- Question 19. How many students A. there is C. there are Question 20. Friction A. were C. are Question 21. Odd one out: A. evening C. learning in your class? B. is there D. are there a force that holds back the movement of a sliding object. B. was D. is B. writing D. playing
