What's the difference between ｢教師」 and ｢先生」?

Question

What's the difference between ｢教師」 and  ｢先生」?

Answer

教師 usually refers to a teacher that teaches at a high school, junior high school and elementary school. Meanwhile, 先生 also refers to a teacher at school as wella a doctor, lawyer, politician etc.

Answer

In old China, 先生=教師. we call 'teacher' as '先生‘ such as ’ 教師=教書的先生‘, In new China, 先生= Sir. 教師=teacher.