They deem that everything has its reason to exist only if it actually exists in this world.

他们认为万事万物只要存在于这个世间，就一定有它存在的理由。

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Chapter 3: China's civil appeals system and its reason.

第三章：我国民事上诉制度的现状与成因。

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It is a serious issue which is worth discussing to explore its reason and find solutions.

究其原因，寻找解决办法，是一个值得探讨的严肃课题。

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One reason for the speech was the state of Arizona's recent passage of its own law against illegal immigration.

VOA: special.2010.07.03

The reason it looks like a tautology, because you look around, nothing seems to have its velocity forever.

其原因听起来像是绕圈子,因为你看看四周,似乎一切都不可能永远运动下去

耶鲁公开课 - 基础物理课程节选

One reason is dualism has always had its problems.

原因之一即二元论总是有自身的局限性

耶鲁公开课 - 心理学导论课程节选

But relenting on this point is cutting journalism clean from its reason to exist.

FORBES: "Call of Duty" - Newspaper of the Future?

So what exactly is this mysterious insurance score, and what exactly is its reason and purpose?

FORBES: How An Insurance Company Determines Your Premiums

That that consciousness could live on in only one of their bodies is both the central tragedy of Just Kids and its reason for existing.

FORBES: Patti Smith Says Goodbye