A rainbow appears in the sky in the morning of senior one language, indicating what day it is today.

Rainbow is formed by the scattering and reflection of sunlight on small round water droplets in the air.

In fact, as long as there are water droplets in the air and the sun shines behind the observer at a low angle, an observable rainbow phenomenon may occur. Rainbow usually appears in the afternoon, when the rain clears. At this time, the air is less dusty and full of small water droplets, and one side of the sky is dark because of rain clouds. However, there is no cloud cover on the head and behind the observer, so the sun can be seen. In this way, the rainbow is easy to see. Another place where rainbows are often seen is near waterfalls. Sprinkling water or spraying fog into the air with your back to the sun on a sunny day is also "as the saying goes,' See the rainbow after the rain'". The appearance of rainbow has a lot to do with the rain these days. "Meteorologists said," the air humidity is relatively high after the rain, and now the rain has stopped. When the sun comes out, the water droplets in the air refract the sunlight and a rainbow is formed. "