Subway car following means that subway employees are responsible for standing at the door, guiding passengers and supervising safety during the operation of subway vehicles. Usually, the staff of subway enterprises take the post of attendant. They need to ensure passengers get on and off smoothly and assist the safe operation of subway trains. This is an important work, because there will be a large number of passengers in the subway during rush hours, and the safe ride of passengers is closely related to the normal operation of the subway. Therefore, following the train is an important post to ensure the safe and smooth operation of the subway. Subway car following means that subway employees are responsible for standing at the door, guiding passengers and supervising safety during the operation of subway vehicles.