Formal:
* 告别 (gào bié): This is the most common and formal way to say goodbye. It literally means "to say goodbye".
* 辞行 (cí xíng): This also means "to say goodbye" but is slightly more formal than 告别.
* 惜别 (xī bié): This means "to bid farewell with regret" and is used when you are sad to be leaving someone.
Informal:
* 再见 (zài jiàn): This is the most common informal way to say goodbye, meaning "see you again".
* 拜拜 (bài bai): This is a very casual way to say goodbye, similar to "bye-bye" in English.
* 保重 (bǎo zhòng): This means "take care" and is a friendly way to say goodbye.
Other options:
* 一路平安 (yī lù píng ān): This means "safe travels" and is a polite way to say goodbye to someone who is leaving on a trip.
* 珍重 (zhēn zhòng): This means "take care of yourself" and is a more formal way to say goodbye than 保重.
The best way to choose the right translation is to consider the context of the situation and your relationship with the person you are saying goodbye to.