而如果这两种介质的密度相差较大，就像空气和水那样，那么大部分的能量将会折射回来，只有一小部分会继续传播进入到新的介质中。

If the two media have really different densities, like air and water, then most of the energy is going to be reflected back, very little of it will keep going and get transmitted into the new medium.

youdao

能量可以穿过杯壁流动，但是我在顶上加了盖子，所以水不能跑出来。

Energy can flow across the glass but I put a lid on top, and so the water can't get out.

youdao

驱动蒸汽机车的能量可以储存在除水以外的其他物质中。

Energy to drive a steam locomotive can be stored in other materials besides water.

youdao