If 3 riders share a Pay-Per-Ride MetroCard, do we need to swipe once and let the first rider to go through the turnstile, and swipe again and let the second rider go through the turnstile, and so on? This is assuming the there is a gate that opens only upon a swipe is complete, therefore 1 rider pays and goes at a time. From what I read, I understand that a card can be swiped multiple times consecutively. Then what? The riders go through the turnstile one by one consecutively without having to swipe the card in between? Does this means there is no mechanical opening of the gate and it's sort of like an honor system, relying on the honestly of the riders? Of course I am not trying to evade fares; I just wanted to make sure we won't get stuck at the turnstile, causing delay for ourselves and other subway riders.