I realize I've given you some difficult mathematics, but--it's not that difficult actually-- but I kind of went through it quickly.

我发现我给了你们一些比较难的数学公式，不过，并不是想象的那么难-,我很快就把它们讲完了。

耶鲁公开课 - 金融市场课程节选

I'm not saying you want a job at an investment bank because it's also demanding and difficult.

我不是说你想在投行工作,是因为它既苛刻有困难。

耶鲁公开课 - 金融市场课程节选

That's a quite difficult argument to pin down does it work or does it not work.

这个论证很难确定,是不是说得通。

耶鲁公开课 - 死亡课程节选

"It's not difficult, but it's very complex, " said Dave Pelz, the former aerospace engineer turned short-game guru.

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"The house is alarmed and there's a security light outside, and it's not difficult to see who's standing outside the door because you can see from inside, " she said.

BBC: Vicar replacing murdered John Suddards tells of her hopes

It's not difficult to imagine a future in which cyber attacks become more frequent or serious.

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