{{Grammar Box}} 

一旦 (yīdàn) is used to express what would happen after a certain condition is met. Usually it is used with 就. This grammar pattern expresses that once one thing happens, something else will happen.

== Structure ==

This structure is similar to the English "once...then," as in "once the company goes bankrupt, your family will lose all its money." 

<div class="jiegou">

一旦 + Condition，Subj. + 就 + Consequence 

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== Examples ==

<div class="liju">

* <em>一旦</em> 我 找 好 的 工作，我 <em>就</em> 会 安心。<span class="trans">Once I find a good job, then I'll be able to relax.</span>
* 这 张 桌子 不 稳定，<em>一旦</em> 发生 什么 小 小 的 振动，<em>就</em> 会 倒塌。<span class="trans">This table isn't very steady. Once there's even a small vibration, it will fall over.</span>
* 学习 计算机 科学 的 学生 很 自信，他们 <em>一旦</em> 毕业，<em>就</em> 会 找到 很 好 的 工作。<span class="trans">Computer science students are very confident. Once they graduate, they will be able to find good jobs.</span>
* 千万 不 要 在 经济 泡沫 中 炒股，<em>一旦</em> 市场 崩溃，你 会 很 后悔 的！<span class="trans">You must absolutely not trade stocks in an economic bubble. Once the market collapses, you will regret it!</span>
 
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Notice in the last example there is no 就. Sometimes you can leave out the 就 and the context that the result will happen is pretty clear.

== Sources and further reading ==

=== Books ===

*[[Common Chinese Patterns 330 (汉语常用格式330例)]] (p. 262)[http://www.amazon.com/gp/product/7802006473/ref=as_li_ss_tl?ie=UTF8&tag=allset-20&linkCode=as2&camp=217145&creative=399373&creativeASIN=7802006473 →buy] 

[[Category: B2 grammar points]]
{{Basic Grammar|一旦|B2|一旦⋯⋯，就⋯⋯|<em>一旦</em> 我 找 好 的 工作，我 就 会 安心。|grammar point|ASGU3ZV1}}
{{Rel char|就}}
{{Similar|"Only if" with "zhiyou"}}
{{Similar|"If…, then…" with "ruguo…, jiu…"}}
{{Similar|Events in quick succession with "yi... jiu"}}
{{Used for|Indicating cause and effect}}
{{Used for|Indicating conditions}}
{{Structure|Conditional Statements}}