哼着老调唱着老歌
[hēng zhe lăo diào chàng zhe lăo gē]
This implies singing oldies music casually and quietly which suggests the nostalgia and longing for past things, like childhood and youth. For those whose English isn’t so good, one would sing songs familiar only to oneself to release one’s emotion or recall happy memories. The internet slang shows users cherish and remember all the days and moments gone by.