你是你，我是我。（Nǐ shì nǐ, wǒ shì wǒ.）You are not me./We are strangers.

Explanation

这句话常用来强调自己和对方立场完全不同，常在跟别人有分歧时使用，意思是我们是完全不同的人，所以我的想法也跟你完全不同。一般有三种用法：第一种用法，对方对你说了你不同意的意见或者建议，自己觉得恼火或无奈，用这句话来反驳对方的意见，表示你说的只是代表你的观点，适用于你但不适用于我。第二种用法，可以在与人断绝关系（朋友，恋人等）时使用，表示从今以后是完全不相关的两个人，一刀两断。第三种用法，可以加入第三人称，如“他是他，你是你”，或“他是他，我是我” ，表示双方的立场和意见的不一致。
This sentence is to say the two persons are having completely different ideas, which is mostly used in an argument. It can be interpreted as “you and I are different, so my opinion is not the same with yours.” Generally it has three usages. Firstly, it can be used to refute others when they bring up the opinions or suggestions you don’t agree to and you feel frustrated and unhappy. It means what the other person said is not suitable to you. This sentence can also be used when you are breaking up with either your friend or lover, which means the two of you have no relationship and are total strangers from the minute on. The third usage is to add the third person “他” to the structure and change the sentence into “他是他，你是你”，or“他是他，我是我”, which also means the opinions of the two sides are different.

Words:

立场lìchǎnɡ:Position,side;
手头紧shǒutóu jǐn:have not the money.

Sentences

1、Jiǎ: Bú shì wǒ bú jiè gěi nǐ qián, shì wǒ zhè liǎng tiān zhēnde shǒutóu jǐn.
甲：不是我不借给你钱，是我这两天真的手头紧。
A: It’s not I don’t want to lend you the money, but I don’t have the money.

Yǐ: Bú yòng duō shuō le. Cóng jīn yǐhòu nǐ shì nǐ, wǒ shì wǒ, wǒ zài yě bú huì qiú nǐ!
乙：不用多说了。从今以后你是你，我是我，我再也不会求你！
B: Save your breath! From now on, we are strangers. I won’t ask for your help anymore!

2、 Jiǎ: Bié kàn le, kǎoshì qián tūjī yíxià jiù xíng le.
甲：别看了，考试前突击一下就行了。
A: Take a break, you just need to review the lessons before testing.

Yǐ: Nǐ shì nǐ, wǒ shì wǒ, wǒ kě bú xiàng nǐ nàme cōngmíng. Wǒ děi hǎohāo kànkan.
乙：你是你，我是我，我可不像你那么聪明。我得好好看看。
B : We are different. I’m not as smart as you are. So I have to start now.

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