Other units measure things like electrical current or amounts of a substance.

其他单位测量诸如电流或物质的量之类的东西。

It involves exposing children to small amounts of a substance they're allergic to, and if it triggers an allergy, patients may need medical treatment right away.

它涉及让儿童接触少量他们过敏的物质，如果引发过敏，患者可能需要立即就医。

A mole is just a unit that’s used to measure the amount of a substance -- in this case, a gas, in terms of the number of molecules.

摩尔只是一个单位， 用于测量物质的数量——在这种情况下， 是一种气体， 以分子数量表示。

A mole is just a unit that's used to measure the amount of a substance -- in this case, a gas, in terms of the number of molecules.

原子是用来衡量物质数量的单位 在这种情况下，就分子数而言，是一种气体。