大家天天在学校里上学,都会遇到这样的情况:下课了,几乎所有的人都开始说话,喊的、叫的,叽叽喳喳,乱糟糟的。如果用一种办法,把这些声音都收集起来再从一条管道里面传送出去,那就只能听到哄哄嗡嗡的声音,其他什么也听不到了。这里只有几十个人,如果是几百人、几千 Everyone attends school at school every day, and they will encounter such a situation: After class, almost all people begin to speak, shout, call, jealousy, and messy. If you use one method to collect all these sounds and then send them out of one pipe, you can only hear the squeaks and hear nothing else. There are only dozens of people here, if they are hundreds or thousands