A laser beam passing through a jet of helium forms a stream of electrons, and a thin metal foil blocks their way.

激光束通过氦射流形成电子流，一层薄金属箔挡住了它们的去路。

Which you can imagine as a stream of electrons that we used as a very sharp pencil that they used to create tiny structures on top of the foil.

你可以把它想象成一股电子流，我们用它作为一支非常锋利的铅笔，用来在金属箔片上制造微小的结构。

Different batteries use different combinations of metals, and sometimes non-metals like graphite, but the basic idea is to use a pair of chemical reactions to generate a stream of electrons.

不同的电池使用不同的金属组合，有时还有非金属，比如石墨，但基本原理都是利用一对化学反应来产生电子流。