Generally speaking, the study time of most graduate students is two years, but some students choose to take credits during the holidays, so that they can finish credits in advance, and some students are willing to study while working, so the study time will be extended. In short, I graduated after completing the credits. Generally speaking, the doctoral degree of the University of Southern California is five years, but it depends on the time for students to take credits and complete their graduation thesis. China's master's degree is not recognized in the United States, so undergraduates can directly apply for a doctor's degree in the United States, which is called a master's degree. If you have studied or graduated in China, you can choose a matching school according to your research direction and apply for credit transfer, which can shorten the time of studying for a doctorate in the United States.