Please choose the correct ending to complete the given sentence: Cars & Other Vehicles: [header] How to use an oyster card [title] Purchase your oyster card. [step] You can purchase an oyster card in a number of places across london. All tube, london overground, and tfl rail stations have them available.

Ending1: In addition, hundreds of newsagents and shops in london can act as oyster ticket stops, allowing you to buy or refill a car. Transport for london (tfl) even has an oyster ticket stop locator on their website : [title] Oyster cards have a £ 5, non-refundable activation fee that is due at the time of purchase of a new card. Ending2: You can buy oyster cards at most major rail stations. You must know the route of the station you're visiting. Ending3: [title] Get an oyster card app if you don't already have one. [step] Start using the oyster card app on the time you want to use it. Ending4: [title] Take your card from the tube station. [step] Ensure you are directly connected to a main station terminal with the oyster card reader.

Answer format: ending1/ending2/ending3/ending4