In casual parlance, a theory is basically an idea or thought.It probably has no carefully collected data to back it up, let alone any rigorous hypothesis testing or experiments.

在非正式说法里，一个“理论”基本上就是一个概念或思想，它可能还没有仔细地收集到支持它的数据，更谈不上有什么严格的假设检验或实验根据。

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Gerard had never touched a rat in his life, let alone allowed one to curl up and sleep in the weave of his sweater.

杰拉德一辈子从来没碰过老鼠，更不必说让一只老鼠蜷缩在他的毛衣里睡大觉了。

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There’s a lot of up-front effort, and no guarantees that the results will even suit your needs, let alone be clean and well structured.

这存在着许多预先努力，但不保证结果恰好适合你的需要，更别说清晰和结构良好了。

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Because if there's more crisis, let alone a break-up, that could easily sink our recovery for a long time, and cause havoc for Britain's banks.

BBC: A good deal for the UK - or the euro?

Yet on September 14th an associate of Mr Fini declared that Mr Berlusconi's former deputy prime minister would never leave the party he helped to found, let alone set up a rival.

ECONOMIST: Silvio Berlusconi under fire: The sultan and the vizier | The

At the time it was tough to get funding for any idea, let alone a new processor that would go up against the incumbents.

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