Here are some ways to say "Thank you" in Korean:

1. 감사합니다 (kam-sa-ham-ni-da) - This is the most common and formal way to say "Thank you" in Korean. You can use it in any situation.

2. 고맙습니다 (go-map-seub-ni-da) - This is another formal way to say "Thank you" in Korean. It's less formal than 감사합니다 but still polite.

3. 고마워요 (ko-ma-wo-yo) - This is a casual way to say "Thank you" in Korean. You can use it with friends or people you know well.

4. 고마워 (ko-ma-wo) - This is an even more casual way to say "Thank you" in Korean. You can use it with close friends or family members.