PhD vs. Undergrad+Masters / 博士 vs. 本科

Xingbo and I were discussing the difference between PhD and Undergrad/Masters. We reached the following analogy.
If you're a undergrad/masters student, and you're given a paper to read, all you're required is to comprehend the technical points in the paper and know how to reuse it. If you're a PhD student, you need to write a significantly improved paper.

我和师弟Xingbo 那天谈了谈 博士和本科的区别。 最后达到了此下比喻：
如果把一篇技术文章给他看， 他只需要理解里面的技术内容还有领会此技术的应用。 但是，一个博士生就需要创造出更好，更深的新技术。