In the same way, evidence must be designed perfectly if it is to frame an innocent person to make him or her seem guilty.

VOA: special.2010.02.21

So, it's perfectly okay to be part of a collaboration, but you've got to make sure that you're pulling your weight.

所以,参与小组讨论是完全允许的,但你要保证你在其中有所作为

耶鲁公开课 - 基础物理课程节选

Well, there's an explanation of how it could be that things that are not themselves perfectly round could remind us, could make us think about perfect roundness.

这也许解释了为什么有些,本身并不是那么圆的东西,会让我们想到正圆这个型相

耶鲁公开课 - 死亡课程节选