Original sentence: Tickets are not routinely checked when entering a station or boarding, but there are surprise inspections on all routes.[15] During night hours, public transport is continued by the Nightline buses operating on all the main routes, generally every half hour.[citation needed] In the most populated areas of Vienna, public transport runs so frequently (even during off-peak hours) that any familiarity with departure timetables is virtually unnecessary
Edited sentence: During night hours, public transport is continued by the Nightline buses operating on all the main routes, generally every half hour.In the most populated areas of Vienna, public transport runs so frequently (even during off-peak hours) that any familiarity with departure timetables is virtually unnecessary.Tickets are not routinely checked when entering a station or boarding, but there are surprise inspections  on all routes