Giving a speech in front of your class can be challenging.

在你的班级面前演讲是具有挑战性的。

youdao

The class can chant very well.

学生们唱得很好。

youdao

The class can be either an interface or a concrete class.

这个类既可以是个接口，也可以是个明确的类。

youdao

"I can say that,anecdotally, virtually all the teachers noticed immediately much more alertness in class, definitely more positive mood.

VOA: special.2010.10.07

By the way, after class, I'm more than happy to stay as long as needed to answer any questions you guys have or to talk about whatever issues you'd like to bring up, but probably what makes sense is for me to power down the computer and pack up and then we can stand out in the hallway and I can answer questions out there, that way the next class can get in and the instructor can work unimpeded.

顺便说一下,课后,我很乐意多待一会,来回答你们的问题,或者讨论一些你们提出的问题,但我最好是,把电脑关掉,收拾好东西,然后在走廊里来回答你们的问题,这样下节课才能照常进行,老师也能正常授课

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

So it's kind of... it's nice that you can choose because I feel like you have a better time in class.

可以自己选课是件很好的事情，因为这样你在课堂上感觉会更好。

高中生活怎么样？ - SpeakingMax英语口语达人

This President says the middle class can't afford higher taxes in the midst of this recession.

WHITEHOUSE: Transforming the American Economy Through Innovation

The super-massive class can weigh millions or billions of stellar masses and reside at the centers of galaxies.

MSN: Existence of middleweight black holes nearly ruled out

Defining the Chinese middle class can be confusing, depending on whom you talk to or which numbers you use.

FORBES: Defining the Chinese Middle Class