that means it is being offered for a limited time at a reduced price.

VOA: special.2009.05.21

I just doubled the indentation each time so you can see it. So each successive call, notice what's happening. The argument is getting reduced. And we're going another level in. When we get down to this point, we're calling it with just a string of length one.

因此每次成功调用注意它的过程,我们的命题不断简化，而且我们不断深入嵌套,当我们走到这一步的时候,我们就是在调用它处理，仅有一个元素的字符串了。

麻省理工公开课 - 计算机科学及编程导论课程节选

It occurs because blood flow gets reduced in that blood vessel and so the heart muscle, which is actively beating all the time, needs large quantities of oxygen provided by blood can't get the blood through the vessel.

发病原因是冠状动脉血流量降低,因为心肌搏动永不停歇,随时需要血液供给大量氧气,发病时血液无法正常流过血管

耶鲁公开课 - 生物医学工程探索课程节选