In recent years, college enrollment is expanding considerably. The makeup of college students and their English proficiency are varied. In order to cater to the needs of students at various levels, the students of Shanghai University of International Business and Economics are divided into four different classes by test score. The content and method of teaching are different among them. At last, the English level of all student has been improved and we achieved the expected teaching goal. Based on a case study, this paper aims to introduce the unique teaching mode of college English at Shanghai University of International Business and Economics and shed new lights on college English teaching across the nation.