如果论点有效，结论为假，那么我们知道至少有一个前提肯定为假。
So if an argument is valid and the conclusion is false then we know that at least one of the premises must be false.
如果最近和家人频频闹意见，心情上下起伏很大，很没安全感，那么我们知道，现在的运势上会有较大的问题出现了。
If the family has been trouble, the mood fluctuation is very big, very insecure, as we know, there will be a larger problem now fortune.
那么我们如何知道哪些光谱模式与哪些元素相匹配呢？
So how do we know which spectral patterns match up with which elements?
那么，我们的胆怯感会导致我们犹豫，行动迟缓，直到我们知道情况安全了才迈步。
Then our sense of timidity can cause us to hesitate, to move slowly, and not to take a step until we know the ground is safe.
如果我们知道一个老顾客会给不少小费，那么我们就要确保他得到良好的服务。
If we know a regular customer is a good tipper, then we make sure he gets good service.
这很令人兴奋，但如果你认为，你什么知道，你不需要学习了，那么你不再属于我们。
It's very exciting, but if you think you know everything you don't need to learn, you don't belong to us. I always need to learn.
我知道我们是两个不那么陌生的陌生人。
那么，我们如何知道文本应该偏移多少，应该放置在距离顶部多远的位置？
So how did we know how much to offset the text or how far down from the top to place it?
那么，我们如何知道何时需要防止引起反感而何时则不必担心？
那么，你知道，要生产动物作为食物，我们首先要生产很多粮食然后收割这些粮食。
Well, you know, to raise animals for food, we first raise alot of grain and then harvest the grain.
如果书中不尊重这荒谬，那么我们应该知道幻念作为权宜之计溜了进来。
If the absurd is not respected in it, we shall know by what expedient illusion enters in.
如果真是这样，那么我们所知道的那个满是恒星，没准儿还满是生命的宇宙也将只是一个寒冷，黑暗的无尽虚空世界中的短短一瞬。
If so, the cosmos as we know it-full of stars and, maybe, full of life-will be a fleeting moment in an endless duration of cold, dark nothingness.
等我们知道了不那么做的后果时，已经为时已晚。
We won't know the consequences of not doing that until it's way too late.
如果它没有保留真理，那么条件或对或错，我们不知道。
If it isn't truth preserving then the conclusion could be either true or false. And we really don't know.
我确定你对努力工作有很多的观点(不论你是为之而奋斗还是试图避免)，那么让我们知道你的观点和想法吧。
I'm sure you've got plenty of views on working hard (whether you strive for it or try to avoid it!) - so let us know your thoughts in the comments...
如果我们要谈论Web应用程序以及如何开发它们，那么我们就需要知道什么是Web应用程序，以及是什么东西使得它们与我们创建的其他应用程序不同。
If we're going to talk about Web applications and how to develop them, we need to know what they are and what makes them different from other applications we might create.
既然我们知道了攻击的基本知识，那么做些什么才能保护我们自己避免这一脆弱性呢？
Now that we know the basis of an attack, what can we do to protect ourselves from this vulnerability?
那么，我们怎么知道别人真实的感觉？要想知道的话，你有几个选择。
So, how do we know what the other person is truly feeling? You have several options for getting this information.
如果错误选择的预计结果是较小的，那么我们应该根据我们现在知道的内容制定最佳决策并继续前进。
If the projected consequences of the wrong choice are minor, we should make the best decision based on what we know now and move on.
但是我们不知道做什么，如果你不帮助我们去理解你，那么我们可能做错事。
But we don't know what to do and we might do the wrong thing if you don't help us to understand.
我们知道，记忆常常在睡眠时被加深，那么，我们的问题是：睡眠对错误记忆有何影响？
We know that memories are often consolidated in sleep, so the question arises: how does sleep affect false memories?
约翰彻勅：如果我们要能有效地适应这种变化，而非仅仅是为了应付重大事件，那么我们需要知道将来会发生什么。
JOHN CHURCH: If we are going to be able to adapt cost effectively rather than in response to major events, then we need to know what might happen into the future.
既然我们已经知道机器中都有什么了，那么我们需要看一下这些资源中哪些分配给了控制台，哪些分配给了虚拟机。
Now that we know what is in the machine, we need to see which of these resources are allocated to the console and which ones are allocated to the virtual machines.
我们当然知道既然我们能用它来打电话，那么音频一定从耳机接口进入了手机。
Of course we know that audio is getting into the phone from the headphone jack, since we can use it to place calls.
所以当我们不明白为什么这对于年轻人有那么大的吸引力时，我们应该知道不能低估和屏幕交互的‘快乐’。
So we should not underestimate the 'pleasure' of interacting with a screen when we puzzle over why it seems so appealing to young people.
如果有相当一部分人选择了“没那么重要”那样的话我们就知道我们需要从证明提高演说技巧所能带来的好处讲起。
If a number of participants click on "it's not that important" then we know we have to start the course by demonstrating the benefits of developing presentation skills.
这方面我们确实很擅长，但是在很多基础工作上并没有做得那么好，而我们并不知道这点。
We're really good at that, but a lot of the basic things we don't do very well, yet we don't know it.
这方面我们确实很擅长，但是在很多基础工作上并没有做得那么好，而我们并不知道这点。
We're really good at that, but a lot of the basic things we don't do very well, yet we don't know it.
应用推荐