When you jump into water, what happens to you?
You get wet. But birds that live on the water, like this swan, don't have the same problem. That's because instead of hair, they have feathers growing out of their skin.
Birds that live on the water, or waterbirds, have different feathers than birds that live on the ground or in trees.
Their feathers feel different, and they grow very close together. Because of this, the water stays on top of the feathers, and doesn't get to their skin.
You can see the drops of water on the feathers of this bird's head. Wouldn't it be great if humans were waterproof too?
羽毛 (yu3 mao2)
防水的 (fang2 shui3 de5)
If you have to ride on a scooter when it's raining, make sure you wear a waterproof jacket.