把官网的回答贴上来,希望有助于其他有同样问题的朋友。The your order 35762665 is a regular ticket (not a supersaver ticket) and is therefore not restricted to a particular train. The Online Ticket is valid in any train, on the selected day of travel and for the printed stretch of journey.On trains within Switzerland, seat reservations are not obligatory. Seats may be reserved in trains which are marked "R" (reservation possible), "RE" (reservation recommended) or "RR" (reservation mandatory) under "comments" in the online timetable. The reservation fee is normally CHF 5.00 per person.