Chinese grammar › HSK 5
Once ... with 一旦…就 — Chinese grammar (HSK 5)
一旦 + Condition，(Subject) + 就 + Result
一旦 (yīdàn) means "once / as soon as (something happens)" and introduces a decisive moment after which the result follows. It often refers to something serious or irreversible. The result clause usually has 就 after the subject.
Examples
| 一旦做了决定，就不要轻易改变。 Yīdàn zuò le juédìng, jiù bù yào qīngyì gǎibiàn. | Once you have made a decision, do not change it lightly. | |
| 一旦失去健康，有再多的钱也没有用。 Yīdàn shīqù jiànkāng, yǒu zài duō de qián yě méiyǒu yòng. | Once you lose your health, no amount of money helps. | |
| 这种问题一旦发现，就要马上解决。 Zhè zhǒng wèntí yīdàn fāxiàn, jiù yào mǎshàng jiějué. | Once a problem like this is found, it must be solved immediately. |