Khun Lin from Sunrise need me to inform you that the airplane ticket from Shanghai to Chicago as your requested below cannot be cancelled and no refund upon the ticket is issued, but if in case you would like to change the trip’s date in the ticket during the weekday (Mon-Thu) she will charge you for the new fare with the extra charge only which is as same as changing the trip’s date in the ticket during the weekend (Fri-Sun). But the extra charge for changing the date during the weekend is more expensive than the weekday.