小朋友们 my little friends，我下面向大家介绍 I will introduce you 一个老爷爷 an old gentleman，如果你听说过他 if you have heard of him，请举手回答 please raise your hand。
大家看 please look at this 我手机上的这张照片 the photo on my phone，就是这个白头发的老爷爷 this old genleman with white hair，谁知道他吗 is there someone who knows him？
好 good，白狐同学举手了 White Fox raised her hand，请回答 please answer。
谢谢 Thank you，这个白头发、白胡子的老爷爷 this gentleman with white hair and white beard 是爱因斯坦 is Einstein，他的完整的姓名 His full name 是阿尔伯特 爱因斯坦 is Albert Einstein，已经去世很多年了 he passed away many years ago，是一位很有名的科学家 as a well known scientist，为我们整个人类文明做出了巨大的贡献 he has contributed to the entire human civilization significantly，很了不起 a great man。
他在世时 When he was alive，也就是说 which is to say，他没有死之前 before he died，有人问过他这么一个问题 someone asked him such a question：“声音的速度是多少 What is the speed of sound？”
哪位小朋友知道什么是声音吗 Anybody knows what sound is？
好，白狐同学你来回答 OK, White Fox, please answer。
很抱歉 I am sorry，回答不完全正确 your answer is not exactly correct，你这是狗叫 you are just barking。
声音 sound 就是我们可以听得到的各种响声 is the various sounds that we can hear，包括 including 打雷的声音 sound of thunder、刮风的声音sound of wind、我们说话的声音our voice when we speak、做饭的时候听到的声音 sound when we cook 等等 etc。
这些声音 these sounds 从你的嘴巴跑到我的耳朵里 when it travels to my ears from your mouth，是需要时间的 take time。要是你站在太阳落山的那个山顶上朝着我喊话 if you yell at me on the mountain where the sun sets，我要过一会儿才听得到 I won’t hear if until after a while，这就是说 which means，声音跑过来 when the sound travels to here，有一个速度 there is a speed，如果我们隔得近 if we are near，那很快就听得到 then very quickly we hear it，要是隔得远 if we are far apart，就需要等一会儿 then we have to wait。
那要是你跑到美国去朝我喊话呢 what if you go all the way to the United States and yell at me？需要好多天 well, it will take days，我才能听得到 before I hear you。
刚才我们提到了速度 Just now we mentioned speed，那么声音的速度是多少呢 What is the speed of sound then？是每一秒钟340米 it is 340m per second。一秒钟是多久呢 how long is a second？大家摸一摸自己的胸口 put your hand on your chest，就在这里 right here，心脏每跳一下就是差不多一秒钟 every heart beat takes around one second。340米是多远呢 how far is 340m？就是我们这里到门前那座大桥的距离 it is the distance between the bridge and here。
刚才说 We were saying，有人问伟大的科学家爱因斯坦 somebody asked great Einstein，声音的速度是多少 what is the speed of sound，这位科学家说 the scientist says，我从来不去记这些东西 I do not carry such information in my mind。
为什么他不去记呢 Why didn’t he？他说 he says，书本 books 可以负责记忆 are responsible for memorizing，我们是人 we are people，是负责思考和创造的 we think, and create。
白狐 White Fox，这句话你听懂了吗 do you understand his words？
没有听懂 No？我们现在先出去 let’s spend some time outside，从这里走到大桥那里 walk from here to the bridge，体会一下声音的速度 experience the speed of sound，回来再讨论这个话题 and we will discuss the topic when we return，为什么爱因斯坦说 why Einstein said，我们不要花很多精力 we do not need to use a lot of energy 记住书本上的知识 to memorize the facts on books，而是要去创造 we should be creating，去思考 and thinking。
现在 now，请大家都戴上 put on your 帽子 caps、手套 gloves，换好鞋子 shoes，去桥上看看 and let’s take a look on the bridge。
