Performance breakthroughs seem to come in two varieties: easy and hard.

性能突破似乎有两种不同的实现方式：简单的和困难的。

youdao

During heavy training there should be a big difference between your easy and hard training paces.

在高强度训练过程中，您的轻松跑和高强度训练应该有很大的配速差异。

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I have learned to defend myself against what is hard; without knowing it, I have also learned to defend myself against what is soft and what should be easy.

我学会了在困难面前保护自己；在不知不觉中，我也学会了保护自己远离细腻事物和简单的事情。

youdao

But the Navajo homeland is harsh country, where it's hard to find good-paying jobs and all too easy to fall sway to alcoholism and despair.

VOA: standard.2010.03.22

Just check, that exactly corresponds to the easy and hard thing we just had before.

验证一下,这和我们之前,选择平坦之途还是崎岖之途是对应的

耶鲁公开课 - 博弈论课程节选

Conversely, if he goes on the hard pass and you defend the easy pass, he's going to lose one of those battalions.

相反,如果他选择崎岖之途,而你却防守平坦之路,那么他仅仅损失一个营的兵力

耶鲁公开课 - 博弈论课程节选

How can you enable customers to make easy things easy and hard things possible?

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This turns out to be both surprisingly easy and surprising hard at the same time.

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Income from wealth is easy to hide and hard to tax -- and perfectly legally.

CNN: Why do the Romneys pay so little in taxes?