Use PowerPoint to crop and arrange these four photos together.

When there are sunlight and water droplets in the sky, the sunlight will be refracted and reflected in the water droplets at an appropriate angle to form a rainbow. The rainbow we see on the ground is actually formed by water droplets of different colors. For example, the red of the rainbow you see is the red light that is refracted and reflected by sunlight in the water droplets and reaches your eyes, and the formation of other colors is the same. In other words, each drop of water that reaches your eye actually has only one color, but the drop of water at different elevation angles will show different colors, so we can see colored rainbows. But because the water droplets of the rainbow usually come from water vapor a few kilometers away, it is not easy for us to prove this phenomenon.
In the early morning of December 15, 2021, I saw a lot of dew on the grass. I found that under different angles, through a long lens, you can see that the same dewdrop reflects different colors. I am happy to adjust the different shooting angles to make the same drop of water reflect different colors-including red, yellow, green, and purple. And put these photos together. I hope this composite photo shows that the colors of the rainbow are actually drops of water from different angles.
My English is not good. I don’t know whether the reasons for rainbow formation can be correctly presented. You can refer to the instructions on the following webpage: https://www.atoptics.co.uk/rainbows/primary.htm