フォーマルなら、
I resigned from my job.
退職いたしました。
resign で退職するという意味になり、フォーマルな表現として知られています。
The Cabinet has resigned. とも言えますね。（[内閣が総辞職した](https://eikaiwa.dmm.com/uknow/questions/109546/)）
カジュアルに言いたいのであれば、
I quit my job.
[仕事やめた。](https://eikaiwa.dmm.com/uknow/questions/51073/)
のようにquitが使えますね！
I want to quit smoking.（たばこをやめたい）など。
I would like to announce that I am no longer under employment at OO.
I am no longer working for OO.
I have decided to part ways with OO.
The most formal of the three I mentioned is, "I would like to announce that I am no longer under employment at OO." If you are posting this on Facebook or some sort of blog, you can begin by letting your readers know that you have an announcement, something like this:
- Recently, there have been quite a few changes in my professional life. I would like to announce that I am no longer under employment at OO.
If you are posting on Twitter and want to watch your word count, you can just stick to the one sentence:
- I would like to announce that I am no longer under employment at OO.
If you preface your announcement with an opening like above, the second option can be worked in like this:
- I would like to take this time to announce that I am no longer working for OO.
Sometimes, when we separate from something (a business relationship) or someone (a long personal relationship, like a marriage), we use the phrase "part ways with." You can use it like this:
- Due to many recent life changes, both personal and professional, I have decided to part ways with OO Company.
- We regret to announce that although we will continue to love and support one another, OOさん and I have decided to part ways.
3つの中でもっとも丁寧な表現は、
"I would like to announce that I am no longer under employment at OO."
〇〇の[社員](https://eikaiwa.dmm.com/uknow/questions/35018/)ではないということを告知でしたいです。
もしフェイスブックやいくつかのブログに掲載したいのであれば、以下のように告知して読者に知らせることができます。
- Recently, there have been quite a few changes in my professional life. I would like to announce that I am no longer under employment at OO.
最近、仕事の経歴に多くの変更がありました。
もはや、〇〇の正社員ではないということを告知したいです。
ツイッターやワード数を見たいのであれば、以下のように1つの文にまとめることができます。
- I would like to announce that I am no longer under employment at OO.
〇〇の社員ではありませんということを告知したいです。
もし、以下のように告知を始めたいのであれば、このように2つ目を選択することができます。
- I would like to take this time to announce that I am no longer working for OO.
〇〇で働いてはいませんということを告知したいです。
時々、何か（ビジネスの関係）や誰か（長い関係、結婚など）と別れる時、「part ways with.」というフレーズが使えます。
- Due to many recent life changes, both personal and professional, I have decided to part ways with OO Company.
プライベートと仕事の両方で、最近生活にたくさんの変化があり、〇〇会社を辞めることを決めました。
- We regret to announce that although we will continue to love and support one another, OOさん and I have decided to part ways.
この告知することを残念に思います。お互いに愛すること、支えあうつもりでしたが、〇〇さんと私は別々な道を進むことになりました。
To whom it may concern: I have resigned from my position at...(place of work)
When we "quit" our job it is a big deal! and we may want to let others know our current position is "unemployed" . We might simply want the world to know of our decision...in a more formal way..."To whom it may concern" adds a flourish:-D
"To whom it may concern: I have resigned from my position at...(place of work)"
私たちが仕事を "quit"（辞める）事は大事ですよね!
そして、人々に自分の今のポジションが"unemployed"（無職）と言う事を伝えたいですね。
世間にあなたの大きな決断をフォーマルな方法でお知らせしたいですよね。
"To whom it may concern"
（担当者の方へ）
これを付け加えると見栄えがします:-D
【例】
"To whom it may concern: I have resigned from my position at...(place of work)"
（関係者の方へ：私の（職場名）での職を辞任いたしました）
I want to inform you that I have retired from (Company name)
I would just like to let everyone know that I have resigned/quit my job at (Company Name).
I have decided to move on from (Company Name).
I want to inform you that I have retired from (Company name). "inform" means to give information or tell someone something
I would just like to let everyone know that I have resigned/quit my job at (Company Name) - This explains that you have left your job and that you are telling everyone.
I have decided to move on from (Company Name). This explains that you have left the company but also gives you the chance to then say what you will be doing next.
"I want to inform you that I have retired from (会社名).
Informは情報を伝えたり、話すことがあることを意味します。
I would just like to let everyone know that I have resigned/quit my job at (会社名)
この表現は、あなたが仕事を辞めたことを、みんなに伝える時に使います。
I have decided to move on from (会社名).
この表現は、あなたが今の会社を辞めたけど、
又別のことをする可能性があることを表しています。"
Since you want to post on the social media, you have to be careful how you write it since this is public.
You can use the above sentences since they are formal ways to say it.
example
"I will be leaving soon "
or
"I am announcing that I am leaving"
or
"I am moving to a different job and will be leaving soon"
"I will be leaving soon "
もうすぐ退職します。
"I am announcing that I am leaving"
退職するのを伝えます。
"I am moving to a different job and will be leaving soon"
違う仕事に変わって、もうすぐ退職します。
The first two are very simple ways to express that we either, "quit," or that we, "resigned," from the position or job we were in before. We can also use the phrase, "no longer," to talk about how this is something that has ended and we are no longer working for a particular company.
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