井水不犯河水。(Jǐngshuǐ bú fàn héshuǐ.)One should care his own business; Stay out of things that don't concern you.

Explanation

“井水不犯河水”是一个成语，意思是彼此没有关系，不互相影响。常用来比喻各管各的，互不相犯。
“井水不犯河水”(jǐngshuǐ bú fàn héshuǐ)is an idiom which means each other does not have relations and influence. It is a metaphor that one should care his own business.

Words:

独立dú lì:independen;
联系liánxì:contact.

Sentences

1、Jiă: Nǐ yào búyào gēn tā shāngliang yíxià zài zuò juédìng?
甲：你要不要跟他商量一下再做决定？
A: Do you need to discuss with him before making a decision?

Yǐ: Wǒ hé tāshì gèzì dúlì de gètǐ, jǐngshuǐ bú fàn héshuǐ,zhè jiàn shì wǒ kěyi zìjǐ zuò juédìng.
乙：我和他是各自独立的个体，井水不犯河水。这件事我可以自己做决定。
B: No, either of us is independent and each one minds his own business. So I can make a decision by myself.

2、Jiă:Cóngcǐ yǐhòu zánliǎ jǐngshuǐ bú fàn héshuǐ, gè guò gè de!
甲：从此以后咱俩井水不犯河水，各过各的！
A: We mind our own business from now on.

Yǐ: Hǎo, yǐhòu nǐ zài yě bié gēn wǒ liánxì le.
乙：好，以后你再也别跟我联系了。
B: Ok, then you will not contact me any more.

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