Currently, Vietnamese is still being used in many foreign language classes in general, and English classes in particular. At universities, Vietnamese is used very often in classes for non-English major students. Using the mother tongue for technical instructions or theoretical issues is considered the easiest way to convey knowledge to students, however overusing the mother tongue will make students unable to There are many opportunities to practice English, thereby hindering the development of English skills for many students. Through learning about the theory of English teaching methods, the author offers some suggestions on using Vietnamese in English lessons for non-majors with the aim of supporting students to develop their skills. their ability to use English effectively.