根据内容选择。
The sun rises in the morning. The shadow is long. And in the evening, the sun goes down. The shadow is long, too. At noon, the sun is high in the sky. The shadow is short. If it is cloudy or rainy, we can't see our shadows. At night, if there is light, we can see our shadows, too. You go, the shadow goes. You run, the shadow runs. But you speak, the shadow can't speak. We can't hear the shadow. We only see the shadow. Some little children don't know what the shadow is. They go, the shadows go. They are very afraid. In fact, the shadows are ourselves.