不是
Pattern
Subject + 不是 + noun phrase
Key words
Core idea
不是 negates identity, category, role, or possession-like identification. It is the negative form of an equating sentence with 是.
Use it when the positive sentence would use 是.
Mini decision rule
If the sentence identifies a person or thing as a noun phrase, use 不是 for the negative. If the sentence describes an adjective, use 不 before the adjective instead.
This keeps “not a teacher” separate from “not busy.”
Examples
我不是老师。
Wǒ bú shì lǎoshī.
I am not a teacher.
这不是我的书。
Zhè bú shì wǒ de shū.
This is not my book.
他不是台湾人。
Tā bú shì Táiwān rén.
He is not Taiwanese.
Common mistakes
Avoid
我不老师。
Use
我不是老师。
When negating identity or category, keep 是 after 不.
Seen in stories
The Comment Section Plan
第二天，公关部整理评论，发现网友关注的并不是失误本身，而是他们处理时的冷静。
The next day, the PR team sorted through the comments and found that what netizens cared about was not the mistake itself, but the calm way it was handled.
The Group Chat Apology
他不是故意出错，而是那天系统刚升级，很多号码看起来差不多。
He had not made the mistake on purpose; the system had just been upgraded that day, and many numbers looked almost the same.