All credits should be completed within the specified time. The standard length of study for doctoral students in Henan University is three years, and if they continue to study for master's degree and doctor's degree, it is two years. You must complete all the credits within the specified time, pass the defense before you can graduate, and publish more than two papers in core journals as the first author. This is a hard requirement and there is no record of academic misconduct. Publishing a paper needs to ensure that the paper is scientific and reliable and cannot be faked.