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一旦

yī dàn
HSK 2.0 Level 5 HSK 3.0 Level 5 Adverb Common

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This word has multiple dictionary entries. Choose the reading or usage you want to review.

一旦
yí dàn Conjunction once; as soon as
一旦
yī dàn Adverb in case (sth happens); if

Definitions

  1. 1. in case (sth happens)
  2. 2. if
  3. 3. once (sth happens, then...)
  4. 4. when
  5. 5. in a short time
  6. 6. in one day

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Word relationships

Related words

2 items
如果
rú guǒ

if

都表示假设条件，但'一旦'强调条件发生后紧接着的结果，语气更强烈。
当
dāng

(onom.) dong

'一旦'可用于表示某个时间点，与'当...的时候'类似，但更强调突然发生的变化。

Synonyms

1 item
万一
wàn yī

just in case

表示假设或条件，但'一旦'多用于某个事件发生后引发的结果，'万一'强调可能性很小的假设。

Usage notes

Common mistakes

'一旦' is often used with 就 to express 'once...then...', as in 一旦开始就不能停止。

Example Sentences

1 shown
一旦 下雨，比赛就会取消。
Once it rains, the match will be canceled.

AI-generated examples are marked with this icon.

Child Words of 一旦

一
yī

one

旦
dàn

(literary) dawn; daybreak