Once language starts to develop from about age 2, they do have a system for symbolic representation and can talk about things which aren't in their immediate environment including the past.

一旦语言从2岁左右开始发展，他们就有了一个符号表征系统，可以谈论过去和现在环境之外的事情。

youdao

She has been beaten only once in six starts.

她参加了六次比赛，只败过一次。

《牛津词典》

The theory sounds eccentric but once he starts to explain the detective work that went into his deduction, the scepticism gives way to wary admiration.

这个理论听起来怪怪的，但一旦他开始解释符合他的推理的侦探工作，怀疑就变成了对他谨慎的赞赏。

youdao

And,he warns there will be outbreaks of diseases such as diarrhea, meningitis and malaria once the rainy season starts in a couple of months.

VOA: standard.2009.03.28

What starts out looking very benign, once you look closer, is pretty fierce and filled with violence, and that's why people want to leave.

乍一看非常良善，一旦仔细看，会发现它粗暴且充满暴力，而这就是人们想脱离的原因。

耶鲁公开课 - 公正课程节选

So, I will point out, in terms of MO theory, because it rigorously does take into account quantum mechanics, it starts to become complicated once we go beyond diatomic molecules.

我要指出的是，对于MO理论，以为它严格的遵守量子力学，所以一旦超过双原子分子,就变得十分复杂了。

麻省理工公开课 - 化学原理课程节选

You have to be much more willing these days to chase momentum once it starts.

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Once construction starts and millions are spent, Mr. Marlin said, subsequent cost "overruns" are the norm.

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Once that starts, we will see a wave of businesses closing up shop and moving elsewhere.

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