Do they have an effective offer and an effective acceptance ? An offer is a proposal or a proposition that will , if accepted , constitute an agreement It can be written , oral or made by action . An acceptance occurs when the offered agrees to the proposal of the offeror on the terms required by the offeror According to the rule of offer , the offer must be communicated to offeree , According to the rule of acceptance , the acceptance must be communicated to the offeror be reliance of the offer , be unqualified and comply with conditions of the offer In this case , Kitty offers to help Jeff by preparing homemade dim sums or pork buns originally . However . Jeff says he cannot pay her but promises her that he will buy her a gold necklace . This is a counter offer Kitty's offer lapses Jeff becomes the offeror and Kitty become the offeree Kitty accepts his offer by conduct that she provides him enough dim sums and pork buns as he required This action is reliance of Jeff's offer . Therefore , as the rules of offer and acceptance are satisfied a valid agreement exists between Jeff and Kitty