However, depending on the context, you could use these phrases:
Formal:
* 잘 지내세요? (jal jinae-seyo?): This is the most common formal way to ask "how are you?" It literally translates to "Are you doing well?"
* 어떻게 지내세요? (eotteoke jinae-seyo?): This is a more polite and formal way to ask "how are you?" It literally translates to "How are you doing?"
Informal:
* 잘 지내? (jal jinae?): This is a casual way to ask "how are you?" It literally translates to "Are you doing well?"
* 어떻게 지내? (eotteoke jinae?): This is a more casual way to ask "how are you?" It literally translates to "How are you doing?"
* 잘 지냈어? (jal jinaesseo?): This is a casual way to ask "how have you been?" It literally translates to "Did you do well?"
You can also use specific questions:
* 요즘 어때? (yojeum eotte?): This means "How are you doing these days?"
* 무슨 일 있어? (museun il iss-eo?): This means "What's up?" or "Anything going on?"
The best choice depends on your relationship with the person you are talking to and the level of formality you wish to use.