以防你感到愧疚或者后悔，如果你看看页面的底部，猜猜你看到了什么？

And just in case you need a little guilt or prodding, if you look at the bottom of the page, guess what you'll see?

youdao

看看右边这幅图，尽情发挥你的想象力，猜猜这两个人在说些什么？

What are the two men doing? What do you think they are saying to each other?

youdao

看看以下照片，猜猜这是做什麽用？后续呢…

Take a look of the photo below, guess what these parts for? then…

youdao

And this is a very fast speed, of course, it's about 700 million miles per hour. So, one way to put that in perspective is to think about how long it takes for a light beam to get from earth to the moon. Does anyone have any guesses? Eight seconds, that sounds good.

当然这是一个非常快的速度，它大约是每小时7亿英里,为了更形象化，我们,看看光从地球到月球,需要多少时间，你们猜猜是多少？,8秒，猜的不错。

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