英语翻译Have you ever heard an echo of your voice?An echo is a r

英语翻译
Have you ever heard an echo of your voice?An echo is a reflected (反射) sound.Stand in a very large,empty hall with nothing on the walls.Then shout.The sounds you make will hit the walls and come back to you.The walls reflect the sounds.These reflected sounds are called “echoes”.We can use reflected sound to make sound travel farther.Hold a watch about fifty centimeters from your ear.You cannot hear it.The sound of the watch travels a short way in all directions.It does not travel as far as your ear.You can make it travel to your ear by using a roll of cardboard (纸板筒).Make the roll of cardboard about fifty centimeters long.Put one end over your ear and hold the watch at the other.Now you can hear the watch because the sound has not gone in all directions.It is reflected down the roll to your ear.A megaphone (喇叭筒) works in the same way.It makes sound travel farther.It reflects the sound into a beam which can travel a long way.In the ship,the sailor uses the megaphone to make his voice travel.Without the megaphone,his voice cannot travel far.We use reflected sound in many ways.We use it to measure(测量) the depth of the sea,for example.Among the animals,bats (蝙蝠) and whales use reflected sound to tell them where they are and what things are near them.

你有没有听到你声音的回声?回声反射（反射）的声音.站在一个非常大,空荡荡的大厅里和墙上什么也没有.然后喊.你的声音会击中墙壁,回到你身边.墙壁反射的声音.这些反射的声音,被称为“回声”.我们可以用反射的声音使声音传播得更远.把手表从你的耳朵上约五十厘米.你不能听到它.该手表发出的声音传播的一小段路四面八方.它并不旅行到你耳朵.你可以去你的耳朵用一卷纸（纸板筒）.使大约五十厘米长的纸筒.把一端放在你耳朵上,看着对方.现在你能听到声音看因为没有在所有的方向.它反映了滚到你的耳朵.一个扩音器（喇叭筒）的作品以同样的方式.它使声音传播得更远.它反映了声束可以走很远的路.在船上的水手,使用扩音器,使他的声音旅行.没有麦克风,他的声音不远.我们用声音反射的方法有很多种.我们用它来衡量（测量）海的深度,例如.动物中,蝙蝠（蝙蝠）和鲸鱼用反射声告诉他们,他们是什么东西靠近他们.