for a song idiom informal
非常便宜地
very cheaply
She bought the bed for a song at an auction. 她在一次拍卖会上以非常便宜的价格买下了这张床。
Because the shop's closing down, most of the stock is going for a song (= being sold very cheaply). 这家商店要关门了，所以大多数存货都廉价出售。