自分のもの

one's own things

→ 自分
phrase Uncommon #19,208
one's own things もの can mean “thing” or “possessions.” The phrase can also mean “one’s own” when referring to something understood from context.
JA: これは自分のものです。
EN: This is mine.

「荷物を落とさないようにするにはそれを自分のものと思って運べ」

If you don't want to drop it, carry it as if it were your own.

— ロシアン・ブラザー (1997)

自分のものを片付けなさい。

Put your things away.

彼は教わったことを自分のものとした。

He made what he had been taught his own.

だって、自分で本を書いたなら、それは自分のものだし、自分の名前を載せるはずだ。

I mean, if you wrote a book yourself, it would be yours, and you’d put your name on it.

パパが自分のものと言うものよ

It's something Dad says belongs to him.

— ROMA/ローマ (2018)

警察は少女達に車が自分のものかどうかたずねた。

The police asked the girls whether the car was theirs.