The explanation may be something rather more mundane: plain old carbon dioxide.

但是对这件事的解释可能是很简单的东西：极普通的二氧化碳。

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The slide above is a perfect example of using very plain design and little effort to create something that actually looks really nice.

上面的片子就是一个极佳的例子，使用朴实无华的设计，毫无费力就创造出一个看起来棒极了的东西。

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One of its most useful functions, also, is to make an interesting dish out of something simple and economical like hard-boiled eggs, plain poached fish, canned food, or leftovers.

酱汁最有用的功能之一就是化“腐朽为神奇”，让白煮蛋，水煮鱼段儿，罐头食品或是剩饭剩菜这些简单实惠的食物显得更好吃！

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There can be fighting without war but there can be no war without an organization that makes it something more than just plain fighting.

就算没有战争,争斗同样可以存在,但没有组织,便没有战争,组织使的战争的意义超出了单纯的争斗

耶鲁公开课 - 古希腊历史简介课程节选

Anyway, isn't there something plain unAmerican about the federal government owning a hefty chunk of Wall Street?

ECONOMIST: Social Security meets Wall Street | The

If you prefer something plain, you can order a Naked Dog.

BBC: London��s gourmet fast food fad

It may seem odd for an investment professional to focus on something as basic as plain-vanilla savings, but before we can be investors we must be savers.

FORBES: Four Ways To Save More Of Your Paycheck