It was in the 1970s that American linguist S.D. Krashen created the theory of "language acquisition". The theories on second language acquisition were proposed based on the study on the second language acquisition process and its rules. Here, the second language acquisition process refers to the process in which a learner with the mastery of his mother language learns another language without its social environment. Due to the close relationship between second language acquisition research and language teaching, the relevant acquisition theories are of great importance for college English teaching, during which teachers are expected to base their teaching on second language acquisition theories to study the rules of college English teaching, to reform the current teaching patterns and methods and to improve teaching quality. This is a significant project to study carefully for college English teachers as well as second language acquisition researchers.