Through the study of the amount of discourse, the choice of words, the number of clauses and the transitivity in online courses discourses from the perspectives of linguistics and ideology, it is found that even in the open courses where authenticity is questioned, the amount of teachers' discourse is still too much, and students do not really become the subject of the class. Teachers in the classroom involved in ideological and political content, have an impact on students' outlook on life. Both new and old teachers should constantly innovate their own classroom teaching methods, instead of forming bad professional habits. These problems indirectly provide reference value for education reform and self‐improvement of teachers.