These incidents took place during a time of intense social and political change in the United States.

VOA: special.2010.02.25

It means that the properties of the system, the properties that describe the system, don't change in time or in space.

它的意思是指，用以描述系统的性质，不随时间或空间改变。

麻省理工公开课 - 热力学与动力学课程节选

it's the study of how languages change over time.

它研究的是语言的历史变化。

我的专业 - SpeakingMax英语口语达人

Senator Kerry said the time had come for a change in U.S.strategy toward Pakistan, with the aim of appealing to the hearts and minds of the Pakistani people.

VOA: standard.2009.05.04

But luckily for us, there's a classical equation of motion that will, in fact, describe how the electron and nucleus change position or change their radius as a function of time.

但幸运的是，有一个,经典方程描述了电子和核子,位置或者它们直接的距离是,如何随时间变化的。

麻省理工公开课 - 化学原理课程节选

"Whether or not they blame Karzai for that personally, I think that there is a general sense among significant parts of the population that it may be time for a change.

VOA: standard.2009.08.03

I'm thinking about a problem, I'm going to show you an example in a second, first thing I'm going to do is say, what is the thing that's going to change every time I run through the same set of code?

我要解决一个问题，我马上会让大家看一个例子，第一件我要做的事情就是,弄明白每次运行同样的指令集时,每次都会改变的东西是什么？

麻省理工公开课 - 计算机科学及编程导论课程节选

But in an economy that has lost jobs for 23 consecutive months, Hall noted that long-term unemployed continued to grow, rising by 293,000 to 5.9 million, with little change in the number of Americans employed part-time but seeking full-time work.

VOA: standard.2009.12.05

Now,that has changed, for sure; but,the centralization of the French government and the domination of Paris over the life of the nation is very difficult to change, over a long period of time.

现在,情况已经发生了改变,但是法国政府的中央集权化,以及巴黎在国民生活中的支配地位,在相当时间段内,都很难得以改变

耶鲁公开课 - 1871年后的法国课程节选

There have been fundamental changes through time that make the role of the central bank evolve and change through time.

试图保持系统的稳定,随着时间的发展，基本的改变发生,使得中央银行的角色演变。

耶鲁公开课 - 金融市场课程节选

It's a time of technological innovation, tremendous technological innovation, so much technological change that half the time it frightened people.

这还是个技术革新的时代,空前的技术革新,如此多的技术涌现,以至于人们有时候是对其感到恐惧的

耶鲁公开课 - 美国内战与重建课程节选