Formal:
* फिर मिलते हैं (phir milte hain): This is a very common and general phrase, meaning "see you again".
* जब तक हम फिर न मिलें (jab tak hum phir na milen): This translates to "until we meet again" and is more formal than "phir milte hain".
Informal:
* फिर मिलेंगे (phir milenge): This is a more casual version of "phir milte hain".
* जब तक फिर से (jab tak phir se): This means "until next time" and is very informal.
Romantic:
* जब तक हम फिर से न मिलें (jab tak hum phir se na milen): This is a more romantic way of saying "until we meet again".
* आपसे फिर मिलने की उम्मीद है (aap se phir milne ki ummid hai): This means "I hope to see you again" and is a more personal expression.
Note: The specific word for "again" (like "phir" or "phir se") can be adjusted depending on the context. For example, you could say "jab tak hum dubara na milen" (until we meet again) instead of "jab tak hum phir na milen".
It's always good to consider the situation and your relationship with the person you are talking to when choosing the best phrase.