Band four is not difficult. It is basically the knowledge of high school English. You need to be familiar with the CET-4 questions and at least know what to take in CET-4. The so-called know yourself and know yourself.
Due to the large number of non-English major candidates and rich vocabulary, on the whole, Band 4 is about 40%. Therefore, it is less difficult for non-English major candidates to take CET-4, which is the basic exam.