By emphasizing the details of a block of eighty seven cents to bargain again and again come remaining Della himself blush so that readers understand the financial difficulties of the situation of this young couple. So its not afford to buy expensive gifts foreshadowed.
In detail, the author's emphasis on the remaining piece of eight cents and seven cents, by haggling over Della's own blushes, makes the reader aware of the couple's financial difficulties.
In detail, the author emphasizes that the only eighty-seven cents left from the bargaining of Della's own blushing, which makes the readers understand the financial situation of the little couple and thus foreshadows their inability to buy valuable gifts.