What exactly that purgation will entail and why Milton's voice needs to be purged at all I think these questions are really the subject of the entire rest of the poem.

这种净化是很有必要的,弥尔顿的语言为什么需要被完全净化,我认为这个问题才是所有剩余诗歌,真正的主题。

耶鲁公开课 - 弥尔顿课程节选

I mean, it's kind of a necessity for a lot of students, myself included, to have these jobs

我的意思是，对于大多数学生而言，
也包括我在内，做这些工作是很有必要的，

再没时间也要挤出来 - SpeakingMax英语口语达人

So that a half circle, instead of calling it 180 degrees, And a quarter circle, instead of 90, It's good to know certain famous angles.

半圆,不说它是180°,四分之一圆,不叫90°,知道一些常用的角度很有必要

耶鲁公开课 - 基础物理课程节选

They're interesting biological reasons for that, but certainly it's relevant, and it's important of course for physicians to be aware of this when they're screening overweight people for Diabetes given that excess risk in the women.

这些生理因素很有趣,也很有意义,考虑到女性的患病风险更高,医生们在为超重人群检查糖尿病时,很有必要注意到女性的患病风险

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

Because sometimes it's useful to think about the payoffs, as coming from "i's" own choice and everyone else's choices.

因为有时候考虑在i和对手,在不同选择下的收益是很有必要的

耶鲁公开课 - 博弈论课程节选

And these are kind of need in the kids.

这对于孩子们来说是很有必要的。

麻省理工公开课 - 媒体、教育、市场课程节选

You guys have also seen vectors, I'm pretty sure, but it is worth going over some properties and some may be new and some may be old.

我很肯定你们曾接触过矢量,但复习一下相关的性质是很有必要的,有些可能是新知识,有些是已经学过的

耶鲁公开课 - 基础物理课程节选