This is the contents answer.

1)

If you are a foreigner and receive a visa for a Korean language training (D-4) course, a bachelor's or master's course (D-2) at a Korean university

- Bachelor's degree is up to 6 years after admission,

- Master's degree is up to 5 years after admission,

- The doctor can stay up to eight years after admission.

If you get a job at a company in Korea, you can get an E-7 (specific activity) professional work visa and stay for a long time.

2) 

In addition, as a foreigner, if you invest more than 100 million won in Korea (establishment of a one-person corporation, etc.) and register as a foreign investment corporation, you can continue to extend your visa while doing business with a D-8 (investment) visa.

3)

If you marry a Korean spouse and get an F-6 (wedding invitation) visa, you can stay for a long time.

If you are eligible to apply for a permanent residence visa (F-5) after staying for more than five years in the above manner.

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