CET-4 and CET-6 are English tests, with a vocabulary of 4,000 and 6,000. The corresponding test difficulty will also vary according to the size of the number. For example, Band 4 is relatively simple, while Band 6 is more difficult than Band 4. So this means that the passing rate of each grade is different. Now, because of the arrangement of teaching work in some colleges and universities, almost all colleges and universities require students who have not graduated to obtain CET-4 certificate. College English Test (CET) is a large-scale standardized test conducted by the Ministry of Education of People's Republic of China (PRC) in 1987. It is divided into four levels, with CET as the basic requirement and CET as the higher requirement. CET is the biggest English test in China. According to the needs of examination reform and the importance of oral English in international communication, the Examination Committee is actively studying and developing a new oral English examination form suitable for large-scale implementation.

Therefore, CET-4 and CET-6 are generally divided into four modules: speaking, listening, writing and writing. I hope the answer will help you.