22 Sound

Sound written by John Lockyer

声音由约翰·洛克耶编写

Listen. Can you hear any sounds? There are lots of kinds of sounds. Some sounds are quiet like when you whisper. dog Other sounds are loud like a dog barking or children shouting. Let's find out what sound is and how it is made.

听。你能听到什么声音吗? 有很多种声音。 有些声音很安静，就像你的耳语。 还有一些声音很响亮，比如狗叫或孩子们的喊叫。 让我们来看看声音是什么以及它是如何形成的。

Sound is made by moving air. When you clap your hands the air around them moves very fast and vibrates. These vibrations go into your ears. clapping A message is sent to your brain. The brain tells you the sound is your hands clapping together.

声音是由流动的空气发出的。 当你拍手时，周围的空气就会快速移动并振动。 这些振动进入你的耳朵。 一条信息被发送到你的大脑。 大脑告诉你这个声音是你的双手在拍手。

earmuffs Quiet sounds make small vibrations. Loud sounds make big vibrations. Very loud sounds can hurt your ears. People who work with noisy things need to look after their ears. hearing aid Some people don't have good hearing. They have hearing aids. A hearing aid makes sounds louder so the person can hear them.

安静的声音会产生微小的振动。 响亮的声音产生巨大的振动。 非常大的声音会伤害你的耳朵。 在嘈杂环境下工作的人需要照顾好自己的耳朵。 有些人听力不好。 他们有助听器。助听器使声音更大，这样人们就能听到。

Your ears tell you where a sound is coming from. The closer you are to a sound, the louder it is. Sound moves very fast, but it is slower than light. That's why you see lightning before you hear thunder. lightning Sound can move through air, water, metal and the ground. There are no sounds in space or on the moon because there is no air there.

你的耳朵会告诉你声音来自哪里。 你离声音越近，声音就越大。 声音传播得很快，但比光慢。 这就是为什么你会先看到闪电，再听到雷声。 声音可以穿过空气、水、金属和地面。 在太空和月球上没有声音，因为那里没有空气。

Animals use sounds to help them. Dolphins and whales talk and sing together. Animals like the bear and the tiger make scary sounds to keep others away. dolphins Bats can't see well. They send out sounds. These sounds come back to them as echoes. The echoes help bats find their way around and find their food. bat

动物利用声音来帮助自己。 海豚和鲸鱼一起说话和唱歌。 像熊和老虎这样的动物会发出可怕的声音来吓跑别人。 蝙蝠看不清楚。 它们发出声音。这些声音以回声的形式传回给它们。 回声帮助蝙蝠找到它们的路和食物。 蝙蝠