Water from high in the mountains falls in many places to the green valley far below.

VOA: special.2009.01.07

You see the radius is high and then it falls.

你看到半径是高的，然后下降。

麻省理工公开课 - 固态化学导论课程节选

You see the radius is high and then it falls.

你看到半径是高的，然后下降。

麻省理工公开课 - 固态化学导论课程节选