Common fouls: obstruction, dangerous play, third-party block, ball played with rounded side of stick, foot kick, raised hit outside the circle; Card framework: green card (warning, possible 2-min temp suspension), yellow card (5-10 min suspension to penalty box; team plays short), red card (full ...
Why people argue about this
People often assume that yellow cards in Field Hockey are just warnings like in soccer, so they don't realize how serious accumulating multiple yellow cards can be until it leads to a suspension - which is actually governed by NCAA-specific rules and not based on the number of infractions alone, unlike red cards which result in immediate ejection.