At the same time, a freshman, on the strength of his or her letter of admission, can only purchase a student ticket once. Those who have bought their tickets had better choose to alter the tickets if their journeys change instead of returning their tickets directly.
同时，新生凭录取通知书只能购买一次学生票，已经购票的同学如果行程有变，最好选择改签，不要直接退票。