Thinking Step 4: 推理第三个人。他听到了前两个人的话，推断出前两个人都想要。加上他自己也想要，所以三个条件都满足。
I was asked a good question: What are these things? What are the，这一点在heLLoword翻译官方下载中也有详细论述
，更多细节参见51吃瓜
Source: https://developers.google.com/maps/documentation/javascript/get-api-key?setupProd=configure#make_request，更多细节参见下载安装汽水音乐
callRAFCallbacks(currentTime); // fire rAF