一旦 (yīdàn) means In a single day (in case - once). Below are 5 sentences on this site that use it — with pinyin, an English translation and audio. All of them were written by hand; none is machine generated.
Dictionary examples
一旦 决定了就别后悔。
Yídàn juédìng le jiù bié hòuhuǐ.
Once you have decided, do not regret it.
Dictionary example · HSK 5 · 一旦
一旦 下雨，比赛就取消。
Yídàn xià yǔ, bǐsài jiù qǔxiāo.
If it rains, the match will be cancelled.
Dictionary example · HSK 5 · 一旦
个人信息 一旦 泄露很难挽回。
Gèrén xìnxī yídàn xièlòu hěn nán wǎnhuí.
Once personal information leaks it is hard to undo.
Dictionary example · HSK 6 · 泄露
坏习惯 一旦 根深蒂固就很难改。
Huài xíguàn yídàn gēn shēn dì gù jiù hěn nán gǎi.
Once a bad habit is deeply ingrained it is hard to change.
Dictionary example · HSK 6 · 根深蒂固
这种关系 一旦 掺进利益就容易变质。
Zhè zhǒng guānxì yídàn chān jìn lìyì jiù róngyì biàn zhì.
Once money gets mixed into a relationship like this it easily turns sour.
Dictionary example · HSK 6 · 变质
Reading these is one thing; producing 一旦 yourself is another. Cloze in Context takes a sentence from this same bank, removes one word and asks you to put it back — beginner, intermediate and advanced.
Questions about 一旦
How is 一旦 used in a sentence?
This page shows 5 sentences using 一旦 (yīdàn, "In a single day (in case - once)"), each with pinyin, an English translation and audio. Every one of them was written by hand for this site.
Are these sentences machine generated?
No. They come from the site's own dictionary examples, graded readers, travel phrasebook and grammar library — all written by a person. A word with no sentence gets no page here, rather than a page of invented ones.
Is 一旦 an HSK word?
Yes — 一旦 is on the official HSK 5 vocabulary list, and you can study it with the rest of that list on the HSK 5 page.
Where can I see the full entry for 一旦?
The dictionary page for 一旦 has its stroke order, its traditional form, every sense the dictionary lists and a character-by-character breakdown. It is linked at the top of this page.
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Read the full entry for 一旦, write a sentence of your own and check it in the Pinyin Annotator, drill it with HSK 5 flashcards, or search the whole sentence bank for another word.
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