CET-4 and CET-6 are the two main levels of college English test in China, which correspond to the primary and intermediate level of English ability respectively. These two tests, managed by the Ministry of Education of China, are mainly used to evaluate college students' English application ability, especially in reading, writing, listening and translation.

CET-4 is the basic requirement of college English teaching, which mainly tests students' basic English knowledge and application ability. The main contents of CET-4 include listening comprehension, reading comprehension, cloze, essay writing and translation. Through CET-4, students need to master a vocabulary of about 2,500 words, be able to understand and use basic English grammatical structures, and be able to conduct simple daily conversations and writing.

CET-6 is a higher requirement for college English teaching, which mainly tests students' comprehensive English application ability. The content and form of CET-6 are similar to those of CET-4, but it is more difficult. It mainly tests students' ability to use English in more complicated situations. Through CET-6, students need to master a vocabulary of about 5,000 words, be able to understand and use complex English grammatical structures, and be able to speak and write English fluently.

Generally speaking, CET-4 and CET-6 are the important standards of Chinese college students' English ability, which plays an important role in improving students' English level, improving their comprehensive quality and meeting the social demand for talents. At the same time, CET-4 and CET-6 certificates are also an important reference for many enterprises and institutions to recruit.