These layers and be added or removed dynamically and you can change each layer as it has a track that lets you change it as a function of time by inserting keys at certain frames in the track.

这些层可以被动态的增加或删除，你也可以对这些层进行改动，因为每层都有一个轨道，你可以在轨道中的特定时间点加入关键帧到达改变动画的目的。

youdao

You can also release the profile from time to time, but be aware of the consequences: it creates a checkpoint that prevents certain changes, that version cannot be deleted, and so on.

您还可以不时地发布这个概要文件，但是要注意所产生地后果：它创建一个阻止某些变更的检验点，那个版本不能被发布，等等。

youdao

PORT WASHINGTON, N.Y. (MarketWatch) — When everyone is certain something is going to happen 10 years from now, you can be sure of one thing: It won't.

纽约华盛顿港(市场观察)当每个人都确定今后10年将发生什么，那么至少有一件事情是肯定的：大家确定会发生的事情不一定会发生。

youdao

And...so those issues added up is a democratic context which you can't be certain of what the policies will be, so all of these make it sort of somewhat trickier than a place like China.

所以，所有因素加起来,就造成了投资者的困惑,你无法确定,下一秒会出台什么政策,这就使得在印度投资比在中国,这样的国家来说棘手多了。

普林斯顿公开课 - 国际座谈会课程节选

If you find such a hole in a bank of snow you can be fairly certain - it is either a mouse or a meteorite.

BBC: Chelyabinsk gripped by 'meteor fever'