They require an exact amount of water,warmth,soil and protection.

VOA: special.2010.02.17

Specifically, we have to take in this exact amount of energy in order to bump the electron up to higher energy level.

特别的，我们严格需要,这么多,来把电子，提升到更高的能级。

麻省理工公开课 - 化学原理课程节选

Specifically, we have to take in this exact amount of energy in order to bump the electron up to higher energy level.

特别的，我们严格需要,这么多,来把电子，提升到更高的能级。

麻省理工公开课 - 化学原理课程节选