英语翻译英文水平不好,麻烦各位了：“我要离开了,但我还会回来的!”汉译英～如果是“我离开了”，有离开的过去式吗

I'm going to leave, but I'll be back again.
老外会这样说!!

I will leave，but I'll be back in the future.

I'm leaving, but I will come back soon.

I want to leave, but I'll be back!

是不太正式的吗？
I got to leave, but I shall be back.
正式一点就说
I have to go，but I will come back.

I will leave ,but I will come back.

leave ,过去式left
quit,过去式quitted
句子翻译,绝对正确
i need to leave,but i will be back
i am going to leave,but i will be back
我将会离开,但我还会回来

i am leaving,but i will be back.
或者是i am gonna leave,but i will be back. gonna=going on，用以上两种进行时表示马上要如何如何，比用will的将来时更符合时态语境，不信去看带字幕的美剧