5. Read and answer.（Wu Binbin 了解了大家的梦之后，产生了很多的疑问，于是他去查阅了资料。请你读一读，帮助他解答困惑吧！）

Why do we dream?
Is dreaming bad for our health?

People always have dreams and scientists say we all need to dream.
Dreams are like short films. They are usually in colour. There are lots of reasons why people dream. Maybe the dreamer is worrying about something. Dreaming is a way of trying to find an answer. Sometimes we dream to keep our brains (大脑) working.
Some people get new ideas about their work from dreams. They think about their work all day and they dream of their work at night.
Sometimes we wake up with a good feeling from a dream. But often we can't remember the dream. Dreams can disappear (消失) quickly from memory (记忆).
Too much dreaming can be harmful (有害的). The more we sleep, the longer we dream. That is why we may have a long sleep and still wake up tired.

1. Why do we dream?
Maybe we are worrying about something, and dreaming is a way of trying to find an answer.
Sometimes we dream to keep our brains working.
Some people who think about their work all day may dream of work and get new ideas about their work from dreams.
2. Is dreaming bad for our health?
No, it isn't. Scientists say we all need to dream. But too much dreaming can be harmful. We may still feel tired even after a long sleep if we have too much dreaming.

我们可以从阅读材料中提取对应关键信息来回答这两个问题，需定位原文相关语句进行整理总结。