HSK 7-9
一经
yījīng
Once; as soon as (formal)
Structure
Subject + 一经 + Verb (2 syllables) + 就/便/即 + Result
How it works
The conjunction '一经' is used in formal or written contexts to indicate that as soon as a particular action occurs, a specific result or change follows immediately. It is typically followed by a disyllabic verb and emphasizes the causal or temporal link between the two actions.
Examples
该项政策一经公布，就引起了社会的广泛关注。
Gāi xiàng zhèngcè yījīng gōngbù, jiù yǐnqǐle shèhuì de guǎngfàn guānzhù.
Once this policy was announced, it immediately drew widespread public attention.
这种新产品一经问世，便受到了消费者的青睐。
Zhè zhǒng xīn chǎnpǐn yījīng wènshì, biàn shòudàole xiāofèizhě de qīnglài.
As soon as this new product hit the market, it was favored by consumers.
合同一经签字，即具有法律效力。
Hétóng yījīng qiānzì, jí jùyǒu fǎlǜ xiàolì.
Once the contract is signed, it becomes legally effective.
Common mistakes
Using '一经' in casual, spoken conversation; it is a formal literary term and should be replaced by '一旦' or '一...就' in informal contexts.
Tip
Note that '一经' is almost always followed by a formal, two-character verb (e.g., 发现, 核实, 批准) to maintain the formal tone of the sentence.
More HSK 7-9 grammar
See 一经 in real Chinese
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