1. Generally speaking, if a school wants to ask for a CET-4 certificate, but hasn't got it by the time of graduation, it can only apply for an extension of graduation.

2. If the school does not require it, but the unit requires it after graduation, you can take another English certificate instead of taking the CET-4 certificate. Because only students can take the CET-4 certificate, they can't take it after graduation. According to the requirements of the unit, they can only take the business English certificate.