A teacher's duty is impart knowledge and educate people. A good teacher should not only know his subject matter well, but also turn his students to morally-sound citizens. 老师的职责是教书育人，一个好的老师不仅要精通课业，同时也要把学生培养成具有良好道德素质的公民。
A teacher's aim is to impart knowledge. 教师的作用是传授知识。
A good teacher should impart wisdom to his pupils. 好老师就应该把智慧传递 给学生.