Idiom
go into one's song and dance (about something)
Theme: EXPLANATION
to start giving one's explanations and excuses about something. (One's can be replaced by the same old. Fixed order.)Please don't go into your song and dance about how you always tried to do what was right.John went into his song and dance about how he won the war all by himself.He always goes into the same old song and dance every time he makes a mistake.