In / from / at (literary postverbal 于)

Structure verb + 于 + place/origin/object/standard

于 (yú) is a cultured preposition that comes AFTER the verb, adding a complement of place, origin, object or standard. It is highly productive in prose and forms near-fixed compound verbs: 在于 ("lie in": 成败在于细节), 源于 ("stem from": 灵感源于生活), 取决于 ("depend on": 结果取决于态度), 限于 ("be limited to": 限于篇幅). In casual speech these nuances are split among 在, 从 and 由, but 于 packs them into a single elegant syllable. It always follows the verb, never preceding the subject.

Examples

成chéng败bài往wǎng往wǎng取qǔ决jué于yú细xì节jié。
Success or failure often hinges on the details.
他tā的de灵líng感gǎn大dà多duō源yuán于yú日rì常cháng生shēng活huó。
His inspiration stems mostly from everyday life.
限xiàn于yú篇piān幅fu，此cǐ处chù不bù再zài展zhǎn开kāi。
Owing to space constraints, we will not elaborate further here.
问wèn题tí的de关guān键jiàn在zài于yú如rú何hé落luò实shí。
The crux of the matter lies in how to put it into practice.

Levels are indicative: they follow the standard Chinese Grammar Wiki (AllSet Learning) progression, not an official HSK 3.0 mapping. We never assign levels by eye.

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