out of necessity

基本解释

In fact, they will have to melt away -- out of necessity on both sides.
事实上，它们也必须消失---也是出自双方的需要。
Out of necessity we could develop bacteria to extract resources directly from the regolith — a useful technology for Earth as well.
如果需要，我们可以培养细菌，直接从表土提取资源——这项技术在地球上也非常实用。
If you think about it, you’ve probably created a lot of new traditions out of necessity or convenience, but you hadn’t thought of them as “traditions” at all.
如果你想想，你会发现自己很可能出于必要或是为了图方便，已经创造出了一大堆新传统，但你之前从不认为它们是“传统”。

Henderson,who is now 63, says he started to make guitars as a young boy,out of necessity.
They claimed they had acted out of necessity; that was their defense.
但他们声称此行为是迫不得已;,他们这样辩护。
耶鲁公开课 - 公正课程节选
Still, many people have clung to the idea of the Bible as a historically accurate document, many times out of ideological necessity. Many fear that if the historical information in the Bible isn't true, then the Bible is unreliable as a source of religious instruction or inspiration.
但很多人仍坚持圣经是正确记录历史的文件,很多时候不是出于意识形态的必要，很多人担心,如果圣经中的历史信息不正确，那么《圣经》,就不再是宗教教育和神灵感应的可信来源。
耶鲁公开课 - 旧约导论课程节选

Some forward-looking cities are leading on solving the energy-nexus equation, some out of necessity.
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