If he tried to do something difficult, he kept trying over and over again until he learned how to do it.

如果他试图做一些困难的事情，他会不断地尝试，直到他学会如何去做。

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Do something difficult means that everyday we should do things that challenge us and take us out of our comfort zones.

做一些困难的事就意味着每天我们应当做一些使我们有挑战、超出我们舒适环境的事情。

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Willpower is the personal strength you have that enables you to do something difficult. Willpower is the ability to control oneself.

毅力是个人拥有的战胜困难的力量，是自我控制的能力。

youdao

That's a complicated thing that accountants figure out and accountants find it difficult to define the earnings of a company, but they do something and they come up with a number.

会计们会计算这个复杂的问题,他们还会发现公司收益很难定义,但是他们会想办法,得出一个数字

耶鲁公开课 - 金融市场课程节选

Prompting someone to do something that is too difficult for them is very frustrating and nudging someone to do something that they are not motivated to do is just annoying.

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