A penalty kick is awarded when a player commits a direct free kick offence inside their penalty area or off the field during play, as defined in Laws 12 and 13. A penalty kick can be converted into a goal. If a player misses a penalty kick, the opposition may choose to take it again. The referee signals for a penalty by raising his/her arm and pointing to one side of the field. The assistant referees also raise their flags to show that a penalty is required. The referee then walks to the center circle and stops to wait for the penalty kick to be taken. On approach to the penalty box, the referee will call out any relevant instructions, such as "take it", "save it" or "no shot". He will also position himself so that he can see the ball at all times while it is in the penalty area. If a player takes too long before kicking the ball, the referee can warn them by calling out "penalty". If the player does not kick the ball immediately, the referee can award a free kick to the opposing team in the center circle. The goalkeeper can block shots from anywhere on the field, but cannot stop a shot directly from a penalty kick (unless it goes out of play).