这其实也告诉我们，怎样找等值面的切平面。

That also tells us how to find tangent planes to level surfaces.

youdao

您能教我怎样找某一主题的书吗？

Can you show me how to look for books on a certain topic?

youdao

你能告诉我怎样找一些有关工业管理的书籍吗？

Could you tell me how to find some books on industrial management?

youdao

What kind of reader are writers in this period looking for, and what do they want from that reader?

作者在这时候要找的是怎样的读者，他们希望从读者身上获得什么？

耶鲁公开课 - 1945年后的美国小说课程节选