Teacher Li, when night turns into morning, is it because the sun and the moon are taking shifts?

That’s a very cute idea. It’s like taking shifts, but the real reason is that the Earth is rotating.

The Earth is rotating? How does it rotate?

The Earth keeps turning slowly. When it turns toward the sun, it becomes daytime.

So when it turns to the side without the sun, it becomes night?

Exactly. At night, we see the moon because it reflects the sun’s light in the sky.

So the moon doesn’t shine by itself?

Right. It’s like a small mirror. The sun is over there, and the moon reflects the light to our side.

I see! So it’s not that the sun and moon are moving around, but the Earth is rotating!

That’s right. So when the day passes, night comes.