HSK 4 grammar · pattern
X是X，Y是Y
X是X，Y是Y — keep X and Y separate
Pattern
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( ) can be left out · other words may come before, between and after
How it works
Repeating each item around 是 (工作是工作，生活是生活) insists that two things be kept apart and not mixed up — "X is X and Y is Y". It stresses clear boundaries between them.
Examples
工作是工作，生活是生活，别混在一起。
Gōngzuò shì gōngzuò, shēnghuó shì shēnghuó, bié hùn zài yìqǐ.
Work is work and life is life — don't mix them.
感情是感情，原则是原则。
Gǎnqíng shì gǎnqíng, yuánzé shì yuánzé.
Feelings are feelings, principles are principles.
账是账，钱是钱，我们算清楚。
Zhàng shì zhàng, qián shì qián, wǒmen suàn qīngchu.
Accounts are accounts and money is money — let's settle it clearly.
Related
See it in a story
In the app, X是X，Y是Y is underlined wherever it appears in the stories you read, and practised with sentences from them. Free.