把...当成...
Reach for this when you want to say someone treats, considers, or regards X as Y — and you want to highlight the act of categorizing itself. It's a specialized 把 construction where the verb is fixed as 当成 ('treat/regard as'). Use it for relationships ('treat me as family'), priorities ('treat exercise as a task'), and mistaken framings ('treated her as a stranger'). Conversational register; the slightly more formal version swaps 当成 for 当作 or 视为.
Structure
Subject + 把 + [A] + 当成 + [B]
bǎ... dāngchéng...
How to Think About It
Plain 把 fronts the object so the verb can act on it; 当成 is the verb that does the acting, and the action is 'classify as.' You're moving A into the mental box labeled B. The 成 means 'into' — A becomes B in the speaker's framing. If you drop 成 and just say 当, you can still be understood, but 当成 is what learners should default to.
Examples
他把我当成了他的好朋友。
Tā bǎ wǒ dāngchéng le tā de hǎo péngyou.
He treats me like one of his best friends.
别把这件事当成小问题。
Bié bǎ zhè jiàn shì dāngchéng xiǎo wèntí.
Don't treat this as a small problem.
她把每天的散步当成一种休息。
Tā bǎ měitiān de sànbù dāngchéng yī zhǒng xiūxí.
She treats her daily walk as a form of rest.
他把我当成了自己的弟弟。
Tā bǎ wǒ dāngchéng le zìjǐ de dìdi.
He treated me like his own younger brother.
别把工作当成生活的全部。
Bié bǎ gōngzuò dāngchéng shēnghuó de quánbù.
Don't treat work as the whole of your life.
她把这只小猫当成了家人。
Tā bǎ zhè zhī xiǎo māo dāngchéng le jiārén.
She treats this little cat like family.
Common Mistake
Learners forget that 把 requires a specific, definite object. Generic 'people' or 'things' without context sounds off — the listener needs to know which A is being reclassified.
他把女孩当成赚钱的工具。
他把那个女孩当成了赚钱的工具。
Don't Confuse With
把 + Object + Verb + Result
Generic 把 disposal — the verb and result vary. 把...当成... is the specific case where the action is 'treat as.'
认为...是...
Pure opinion ('I think A is B'). 把...当成... emphasizes the treating/handling behavior, not just the belief.
看作...
More formal/written. Use 把...当成... in speech, 看作 in essays.
把 + Object + Verb + Result
Generic 把 sentence where 当成 is replaced by any action verb ('把书放在桌上'). Use 当成 specifically for identity assignment, not physical actions.
把 + Object + 当作 + Noun
Near-identical meaning, slightly more formal. Use 当作 in writing; 当成 sounds more conversational.
Practice
Fill in: 别____这件事当成笑话。
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把
Fill in: 他把锻炼当____任务，反而觉得有压力。
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成
Arrange: 把 / 朋友 / 他 / 当成 / 我 / 了
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他把我当成了朋友。
Translate to Chinese: Don't treat work as your whole life.
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别把工作当成你的全部生活。
Write a sentence using 把...当成... about how someone treats another person or thing.
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她把这只猫当成了家里的孩子。
Fill in the blank: 他 ____ 我当成最好的朋友。
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把
Fill in the blank: 她把这本书 ____ 了宝贝。
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当成
Arrange into a sentence: 我 / 把 / 当成 / 这个 / 城市 / 第二个家
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我把这个城市当成第二个家。
Translate to Chinese: Don't take his joke as the truth.
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别把他的玩笑当成真的。
Use 把……当成…… to say how someone treats you or how you treat something.
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我的老师把每个学生都当成自己的孩子。
Hear It in Real Episodes
This pattern appears in 3 Fluentide episodes. Press play to hear the sentence:
他把女孩当成了赚钱的东西。
He treated the girls as objects to make money.
BBC Exposes Epstein's Brazil Modeling PipelineElementary
把锻炼当成任务，你还是会觉得有压力。
Treating exercise as a task, you will still feel pressure.
China Urges Workers to Relax After WorkIntermediate
如果你喜欢这里的生活，大家就会把你当成朋友。
If you like the life here, everyone will treat you as a friend.
John Legend Explores Beijing HutongsElementary
Related Grammar Patterns
Acquire by listening
Hear 把...当成... in real Chinese, not in a textbook.
Fluentide picks the next news episode at your level, so this pattern shows up again and again in real context. The transcript marks it, the audio drills it. Free to start.