Today we talk about something found in water – waves. Surfers are experts at riding waves in the ocean.

今天我们来谈谈水中的东西--波浪。 冲浪者是在大海里乘风破浪的高手。

This phenomenon should work for all kinds of waves — not just light, but also sound and even water waves.

不仅是光波，像声波甚至水波等所有波应该都会产生这种现象。

You have probably seen water waves.

您可能见过水波。

But even in an ideal water wave, the molecules do drift a bit in the direction of wave motion.

但即使在理想的水波中，分子也会在波浪运动的方向上稍微漂移。

Much like a boat in water, a plane in the air leaves a wake behind it, only instead of swirly water waves, it's swirly air waves, and if you try to water-ski in it, you'll die.

就像水中的船一样， 空中的飞机在身后会留下尾流，只不过那不是旋转的水波，而是旋转的空气波， 如果您试图在其中滑水，您就会丧命。