It is rude to laugh on our friends. the underlined part that needs correction80/80Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction.It is rude to laugh on our friends.isrudelaughonGiải thíchĐáp án đúng là D. on => at. Cụm “laugh at someon”: cười vào mặt ai