A teacher is a person who helps people to learn. A teacher often works in a classroom. ... Most teachers use a variety of methods to teach. Teachers often explain new knowledge, write on a blackboard or whitebo ard, sit behind their desks on chairs, help students with their work, or mark students' work. Teacher play an important role in our life to become successful in career and business. A good teacher helps us to become a good human being in society and a good citizen of the country. + more - less