敵を知り己を知れば百戦危うからず。

Know your enemy and know yourself, and you will never be defeated in a hundred battles.

己の欲せざる所は人に施すことなかれ。

Do not do to others what you would not want done to yourself.

彼は己の力を過信して失敗した。

He failed because he overestimated his own abilities.

己のような奴に何がわかる。

What would someone like you understand?

己は何様のつもりだ。

Who do you think you are?

己のせいで計画が台無しだ。

Thanks to you, the whole plan is ruined.

己、覚えていろ！

Damn you, you'll pay for this!

己、よくも裏切ったな！

Curse you, how dare you betray me!

己、またしても逃げられたか。

Damn it, he's slipped away from me again.

十干は甲、乙、丙、丁、戊、己、庚、辛、壬、癸と続く。

The ten stems run jia, yi, bing, ding, wu, ji, geng, xin, ren, gui.

己は五行では土に属する。

In the five-element system, the sixth stem belongs to earth.

二〇一九年は己亥の年にあたる。

2019 was a year of the Earth Boar in the sexagenary cycle.