Sleeping sickness is spread by a parasite that infects the central nervous system and,if left untreated, moves to the spinal column and brain, resulting in mental confusion and eventual death.

VOA: standard.2010.04.05

OK, so w, first of all, work is being done to the system on the left hand side here.

好的，首先,我们通过左边对系统做功。

麻省理工公开课 - 热力学与动力学课程节选

If you're an inertial observer, then in your system of reference, objects left at rest will remain at rest.

如果你是惯性观察者,那么在你的参考系内,静止的物体会保持静止

耶鲁公开课 - 基础物理课程节选

Then, after you define what your system is, whatever is left over of the universe is the surroundings.

当你定义了你的系统后，宇宙的其余部分,就是环境。

麻省理工公开课 - 热力学与动力学课程节选

And just like in the decimal system, 0 as many zeros on the left that you want.

就像在十进制中，任意放置。

哈佛公开课 - 计算机科学课程节选