不知你注意到了没有，夏季里，当瓢泼大雨倾泻而下时，水塘里的水面上会冒出一个个的小水泡，转眼间，这些小水泡又像肥皂泡一样在水面上滑动起来。有时候，水面上还会翻滚出一个个小水珠。这种有趣的现象并不常见，如果你偶然能亲眼目睹这一有趣的现象，倒也是一件快事。

I don't know if you notice that in summer, when the heavy rain pours down, small bubbles will appear on the water surface of the pond. In a twinkling of an eye, these small bubbles will slide on the water like soap bubbles. Sometimes, the water surface will roll out a small bead. This kind of interesting phenomenon is not common. If you can see this interesting phenomenon by chance, it is also a pleasure.

其实，这是水面张力搞的鬼。当水塘里的水被油污染后，水的表面张力就会变小，有时就会起泡，水面上有层薄油膜时，雨点就会在上面滑动。

In fact, this is caused by the surface tension. When the water in the pond is polluted by oil, the surface tension of the water will become smaller, sometimes it will bubble. When there is a thin oil film on the water surface, the raindrop will slide on it.