在人与人的交往过程中，第一印象起着重大作用。这种由初次见面时所形成的对一个人的印象，被称为“首因效应”。教学实践表明：教师留给学生的第一印象如何，容易使学生产生一种“先入为主”的心理定势。教育心理学中也十分强调：“教师给学生的第一印象，对教师威信的形成有? The first impression plays a major role in the process of person-to-person interaction. This impression of one person from the first meeting was called the “primary effect.” The teaching practice shows that the first impression that the teacher has left for the students is that it is easy for the students to produce a “priority-based” mental orientation. In educational psychology, it is also very emphasized: “What is the first impression that teachers give to students and the formation of teachers’ prestige?