We can never just have it there before us or, as I say, if we can--if we can--it's a very, very difficult act of concentration.

我们永远不能只面对着它，或者，要我来说，如果我们可以的话，那将需要高度集中注意力，这是很难的。

耶鲁公开课 - 文学理论导论课程节选

It's a tough course.

这是一门很难学的课程。

建筑学专业教授 - SpeakingMax英语口语达人

They might have to be formulated as very small steps, in order to do that, but you could.

他们那被构造出来，这些过程必须很小，这好像很难，但实际上是可以做到的。

麻省理工公开课 - 热力学与动力学课程节选

It's very difficult even to keep in mind the conceptual difference between these two sorts of supplement.

要记住,这两种补充的不同是很难的。

耶鲁公开课 - 文学理论导论课程节选

These cells are rare and so it's been hard to identify them, that's part of it.

这些细胞太少了,所以很难找到,这是原因之一

耶鲁公开课 - 生物医学工程探索课程节选

It was becoming absolutely impossible, in fact, or at least much, much harder, to claim that there was a single expression of religious truth to which the English nation could consensually subscribe.

实际上，这是绝对不可能的，至少也是很难断言称,这种宗教真理是,整个英国都能勉强赞同的。

耶鲁公开课 - 弥尔顿课程节选

This is necessary, it's hard to find holes in a Nobel Prize worthy idea.

这是很必要的，在一个获得诺贝尔的想法中,很难发现漏洞。

麻省理工公开课 - 化学原理课程节选

Because as a young, four or five-year-old company, if we're trying to attract somebody from a company that's been around since before I was born, that is in the computer industry, that's pretty hard.

因为作为一个只有四五岁的年轻公司，如果我们想要吸引大家的注意,尤其是在公司创立之前，这在电脑行业是很难的。

斯坦福公开课 - 戴尔CEO-Michael.Dell谈创业和发展课程节选

It's hard to predict, my guess will be the latter.

这很难预料，我猜是后者。

普林斯顿公开课 - 国际座谈会课程节选

But finally, Reiner says, well, thank you for visiting us, it's all very wonderful, but you know our audience would really like to know; it seems like a simple question but it's awfully hard to understand, but how can a great, big, enormous, heavy thing like this airplane get off the ground?

但最后 雷纳说到,谢谢你的来访,太棒了,但你知道吗,我们的观众非常想知道,这问题貌似简单,但却很难让人明白,问题是,像这么一个巨大且沉重的飞机,是如何飞起来的呢

耶鲁公开课 - 古希腊历史简介课程节选

It's a secret number so that if Julius Caesar scrambled his message with the key 13, well, then the recipient had better know what that number is or realistically, -- and this is why it's kind of hard to buy -- into some of these age old algorithms, -- what would an alternative approach be to figuring out Julius Caesar's messages to his generals if he didn't know that secret number was 13?

它是一个机密的数字，以至于,如果凯撒大帝使用密钥13加密了它的消息，然后接收者最好知道那个数字是什么,实际上--这就是为什么很难,破解这些古老的算法-,有什么变换方法使凯撒大帝的将军,可以解密凯撒大帝的消息，如果他不知道,那个机密数字是13呢？

哈佛公开课 - 计算机科学课程节选

Not too many people are willing to see this, and perhaps it is hard to see, because Hazel Motes is such an admirable nihilist.

没有很多人想看，或者说是也许很难看到这封信，因为Hazel，Motes是,如此一个的虚无主义者。

耶鲁公开课 - 1945年后的美国小说课程节选

So it's very difficult, but what I come down to is that you just have to place your energy on your breath, and every time you notice your awareness drifts to somewhere else, you have to recognize this drift and let it go.

因此这很难，但我总结的方法是,只需要把能量集中到呼吸上，每次注意力不集中,飘到别处时，要意识到意识的涣散，并放手不管。

普林斯顿公开课 - 人性课程节选

Take me out to the park, etc... " It's amazing that that melody has become as popular as it has given the fact that it's really hard to sing.

带我出去逛公园,等等,奇怪的是,这段旋律,很流行,而事实上,它真的很难唱

耶鲁公开课 - 聆听音乐课程节选

This proves to be really difficult in the real world because in the real world it's hard to pull apart genes and environments So, you and me will have different personalities ? Why?

这在现实中是很难区分的,因为现实中很难,把基因和环境分开来讲,你和我有不同的性格,为什么？

耶鲁公开课 - 心理学导论课程节选

So essentially, each of these orbitals come from linear combinations of all of the original orbitals, and it's hard to picture exactly how that happens, but one that you can at least start to get an idea is if you think about combining the 2 s and the 2 p z here, which is not quite accurate because of course, we're combining all of them.

本质上，这些轨道每个都来,自原来所有轨道的线性组合，我们很难想象这是怎么发生的，但你们可以至少有个概念,如果你们考虑2s和2pz轨道的结合，这当然是不太准确的，因为我们要把所有的都组合起来。

麻省理工公开课 - 化学原理课程节选