A warning, indicated by a verbal admonishment, or a caution, signalled by showing a player or substitute a yellow card.
A red card, or ejection
They are technically called assistant referees.
They were previously called Linesmen, now they are officially called Assistant Referees, or Referee's Assistants.
3 referees are in soccer and football
Green card in soccer means that when a player respects the referees' decision and be a sportsmanship person
When a football player gets a red card or yellow or out of bounds.
The referee can warn a player in two ways: a verbal warning, or a yellow card.