礼貌问候语英文歌

Hey there! Remember that time in 2015 when I was teaching English to a group of teenagers in a small town in China? We were jamming out to a song in the classroom, and one of them asked me, "What's that song? It's so catchy!" I replied, "It's a classic English greeting song called 'Hello, Goodbye' by The Beatles." They were all excited, and we spent the next 20 minutes trying to learn the lyrics.
等等，还有个事，我突然想到，这首歌的旋律真的很适合作为问候语的背景音乐呢。
You know, it's funny how a simple song can bridge language barriers and create a fun learning environment. Just imagine, a classroom full of laughter and the sound of young voices singing, "Hello, goodbye, hello, goodbye..."
So, what's your favorite English greeting song?