Yes, you can take the exam indefinitely, but you should consider the time to apply for a degree certificate. First, the degree certificate must be processed within 5 years after obtaining it. You take the exam indefinitely, and it will be difficult to do it after this time. Second, the degree certificate must be well written.

To sum up one or two points, there is no limit to the examination, but if you want to get a degree certificate, you must get good grades in your thesis within five years of the examination.

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