What are the rules of American football?

First, the basic rules of American football

Rugby is a sport whose length is measured by yards, and every inch of land is contested on the field. "Code" is an English unit of measurement, which is used to record the moving distance between the player and the ball on the court. The team's success depends on how many yards they have advanced. The official football field of the National Football League (NFL) is a rectangular court with a length of 120 yards (1 10 meters) and a width of 53 yards (1 feet (49 meters). Most gymnasiums are outdoor and covered with grass. Some stadiums-mostly indoor gymnasiums-will also use artificial turf.

Let's take a look at some standard features of professional football fields:

Edge-refers to the boundary line with the width of 1.8m, and one on each side of the site runs through the whole site.

End line-An end line is a 1.8m wide boundary line connecting two parallel sides. The end line and the side line form the rectangular frame of the stadium. Both ends of the terminal line are respectively provided with benchmarks.

Terminal area-Terminal area is two areas with the width of 10 yard (9m) within the terminal lines at both ends of the site. The end zone behind each team is its own end zone, and the end zone in front of the team is the opposite end zone.

Score line-the score line is a 20 cm wide line that runs through the front of the entire end area. There are also two positions at both ends of the score line.

Code line and code mark-there is a distance of 100 yards (9 1 meter) between the two score lines, and the code marks of each code are marked on both sides of the field. Draw a solid white line from edge to edge every 5 yards, and mark the code number on the code line every 10 yards (i.e. 10, 20, 30, 40, etc.). These criss-crossing lines have earned the football field the nickname "gridiron".

Gogoal goal post-located in the middle of the back of the end zone, it is a 3-meter-high post connected with the horizontal goal crossbar. The two ends of this 5.5-meter-long crossbar are connected by a vertical club, and its top end is 9 meters from the ground. The top of each vertical stick is tied with a belt with a width of 10 cm and a length of 107 cm.

The most basic equipment in football match is football. The official football of the National Football League is hand-made by Wilson Sporting Goods Company. It is an oval sphere, about 27.9 to 29.2 cm long. The circumference of the long axis of the football center is about 72.4 cm, and the circumference of the short axis is about 54.6 cm. The weight is about 397-425g. Rugby consists of an inflatable polyurethane airbag lining and an outer cowhide sleeve, which is stitched with gridcord. Olive rope is cotton thread wrapped with vinyl resin. There are three layers of jackets sewn in the leather case, which are used to protect the airbag and help the football keep its unique slender shape. The protruding part of the airbag is connected with an air valve passing through the leather sleeve, which is convenient for inflating the ball.

When we have the approved equipment and set up the venue, we can start the game. The NFL game is divided into four quarters, with a long half-time break between the second and third quarters. If the two teams draw in four quarters, there will be 15 minutes of overtime. In overtime, the team that scored first won.

Although the total game time is only 1 hour, a game usually lasts 3 to 4 hours. Teams may stop timing because of out-of-bounds, passing mistakes or timeouts (teams have three timeouts in each half). When the "2-minute warning" appears 2 minutes before the end of the second and fourth sections, the timing will also stop.

Second, the position of American football players on the court.

The NFL roster allows up to 53 players per team to register. At any time, each team is only allowed to play 1 1 players. To understand the NFL team roster, you must identify three groups in each team: offensive group, defense group and secret service group. Each team has a special position, and players in each position need to master special skills. Let's take a closer look at each position.

Attack group

The offensive team of the team is responsible for attacking the opponent's end zone with the ball on the court. To this end, the attacking players pass each other or break through with the ball. The following are the basic offensive positions.

Quarterback (QB)-This player throws the ball to the catcher or hands it to the running guard. The quarterback is also called "the general on the court" because he is the commander on the court.

Photo courtesy of philadelphia eagles team.

Philadelphia quarterback Donovan? Mcnab

Attack the inside forward-this player prevents the opposing defender from going forward to capture and kill the quarterback and running back. The specific positions of the inner front include:

Center (C)- The center stands in the middle of the inside attack. The player threw the ball between his legs to the quarterback.

Two players (LG/RG) stand on the two wings of the center and are divided into left-back (LG) and right-back (RG).

Interception device (LT/RT) is located on the outside of each protective device. Each team has two interceptions: left interception (LT) and right interception (RT).

Receiver-The receiver walks along site run and catches the ball thrown by the quarterback. According to its position on the court, the receiver is divided into receiver (WR) and tightener (LTE/RTE).

Running guard-The running guard takes the ball from the quarterback and breaks through the opposing court. According to the formation (arrangement) of attacking players, running guards are divided into temple guards (TB), half guards (HB) or full guards (FB).

Photo courtesy of Hank Young, chief photographer of Kansas City Chiefs.

Kansas City running back pastor Holmes is sprinting to the frontcourt.

National defense group

When the team has no ball, it has to defend, that is, do everything possible to prevent the other team from scoring. These players must trap the attacking players with the ball and stop them from moving forward. The defender will try his best to steal the ball from the attacker.

The following are the basic defensive positions:

Defensive forwards-they try their best to put pressure on the opposing quarterback, try their best to catch the ball before it passes, and try their best to stop running forward. There are usually three or four defensive strikers on the court. Specific locations include:

Le/ stand outside the defensive line again and try to hold the attacker's interception.

Pointer (NT)- Located in front of the football.

Defensive interception (LDT/RDT)-Stand opposite the defender of the attacker and try your best to pierce the attacker's front line.

Line guard-If there are four defensive forwards, there will be one central defender (MLB) and two outside defenders (OLB). If there are only three defensive forwards, two inside guards (ILB) and two outside guards will be arranged. Their duty is to support the defensive forwards, catch the running guards of the attacking side, and sometimes keep an eye on the receiver of the other side.

Photo courtesy of philadelphia eagles team.

Philadelphia defender Carlos emmons (player 5 1)

Corner guard (CB)- The role of corner guard is to prevent the receiver from receiving the quarterback's pass.

Central defender-the central defender is located at the end of the defense line, aiming to prevent the opponent's long pass or running breakthrough. Strong defenders (SS) line up on the side of the court where there are more attacking players. The patrol guard (FS) is the rearmost middle defensive position in the defense line.

Special agent team

Photo courtesy of philadelphia eagles team.

Philadelphia football player David Axe.

If the team must play football, it should use the secret service team. This group includes the team's kickers, attackers, and players who are responsible for running around the court to catch and kill the return attackers (see below).

Kicker-after a touchdown, you can kick the ball over the club to score, and you are also responsible for kicking the ball to the other side to start the game.

Kicker-If the team can't advance enough yards on the field, the kicker will be responsible for kicking at will.

Striker-When kicking off or abandoning the ball, the striker is responsible for catching the ball and returning as far as possible. Players can score a touchdown in the counterattack.

In the next section, you will learn how the team moves forward and how the offensive distance system works.

In football, toss a coin to decide which team will take over the first game. From the kick-off, the two teams began to compete for the ball right. Holding the ball means that the player who holds the ball is the attacker.

Photo courtesy of San Francisco 49ers.

Fred Beasley, San Francisco defender

Teams can get the ball in the following ways:

Catch the kick-off-In the first half or after one side scores, the other side is responsible for catching the kick-off.

Force the opponent to make a mistake-one side catches the ball dropped by the other side (loses the ball) or intercepts the ball thrown by the other quarterback (breaks the ball).

Safe ball-if a player is killed by a tackle in his own end zone, that is, the end zone he defends, the other side will kick the ball at will.

Abandon kick-the defender stops the attacker from advancing 10 yards in three attacks, and the attacker chooses to kick or abandon kick to the opposing team after the third attack.

Offensive and defensive exchange-if the attacker can't push the ball 10 yards in four attacks, he must give the ball to the other side.

For those who are new to American football, the last two items mentioned above may be difficult to understand. One of the most puzzling concepts of American football is the offensive distance system. Every time the team takes the ball, it can get a round of four attack opportunities to push the ball 10 yards. If the team can push the ball 10 yards or more in four attacks, the team will get another round of four attacks 10 yards, and so on. For example, if the team advances 3 yards in the first attack, then as long as it advances 7 yards in the second attack, it will gain the right to attack in the next round; If the team advances 5 yards in the second attack, then to gain the right to attack in the next round, the third charge only needs to advance 2 yards; If the team advances 2 yards or more in the third attack, it will regain the offensive right in the next attack, and make the first attack again, and strive to advance 10 yards in the fourth attack.

After each attack, the referee decides how many yards the team will advance or retreat (if the player holding the ball is caught by the opponent behind the line of scrimmage, the team will retreat by the corresponding number of yards, and the line of scrimmage will be discussed later). Then the referee put the ball at the end of the team push. This point determines the position of the scuffle line. The line of scrimmage is a virtual line across the court, and it is also the starting point of each attack by the attacker. The referee of the first team on the sidelines holds the chain of 10 yards and marks the position of 10 yards that the team must advance in order to get a new round of first attack opportunities. In the fierce competition, sometimes the measuring chain is brought into the field to measure the distance between the ball and the 10 yard sign. The front end of the ball must touch the beam connected to the end of the chain, so that the attacker can get a new chance to attack for the first time.

If the team can't advance 10 yards in three attacks, they may choose to abandon the ball and kick it to the other side. If you don't choose to give up kicking and take advantage of the fourth attack opportunity, or "strive for victory", then the attack must reach the 10 yard mark, otherwise you will give the ball to your opponent. In order to push back the starting point of the opponent's attack, the team often chooses to abandon the kick, so that the opposing team must attack a longer distance to score. The party who receives the kick can fight back, that is, the attacker catches the ball and launches a running attack. The football team wants to kick the ball as far as possible, and catch and kill the opponent's attacker as soon as possible when attacking back on the court.

Fourth, the football end zone.

There is only one purpose of this kind of pushing and moving bull ball: to take the ball across the opponent's scoring line and score a touchdown.

Photo courtesy of philadelphia eagles team.

Philadelphia eagles's runner, Dustin Sterley, attacked with the ball.

The opponent's scoring line is the goal of moving in this direction. Once any part of the ball touches the edge of the scoring line, it is considered to have entered the end line area and scored a touchdown. You often hear commentators say that the ball has crossed the end zone plane, which means that the ball has crossed the score line.

Touchdown is just one of the scoring methods in football. After the touchdown, the team can also kick a penalty to get an extra point, or try to break into the end zone again by dribbling or passing the ball to get a binary conversion. When trying to score two points, the team has only one chance to attack.

The following table comprehensively introduces various scoring methods and corresponding scores:

A score is a score.

Touchdown (TD) takes the ball into the opponent's end zone or receives a pass in the end zone. 6 points

After another touchdown, kick the ball over the part between the two vertical clubs of the opponent's goal post. 1 point

Two-point conversion brings the ball into the opponent's end zone or receives a pass in the end zone. 2 points

The penalty kick kicked the ball over the part between the two vertical sticks of the opponent's goal post. 3 points

The members of the security team capture and kill the attacking members of the other side in the end zone. 2 points

The team must kick the ball to the other side after scoring a penalty or a touchdown and completing an additional point or two-point conversion attack. The only exception is security. Teams with safety points can kick and get the ball at will.

Rugby referee

The football match is actually composed of three parties, and the third party is the referee group. They also wear uniforms: black and white vertical shirts, white trousers and white or black hats. These people are responsible for enforcing the rules of the NFL Rules Committee. The referee group consists of six people, each with its own duties:

Referee-He is the referee on the court. He is responsible for sending out the foul signal and has the final decision on the interpretation of the rules. If you watch the NFL game, the referee is the referee who announces the foul and punishment every time.

Arbitrator-He stands about 5 yards behind the melee line and is responsible for checking the players' equipment and behavior.

Sideline referee-He is responsible for judging the player's moving foul when he is on the line of scrimmage. He also tracks down fallen players and manages linesmen.

The dividing line-he assists in timing in the game and controls the official time on the field. In addition, it also assists the sideline referee to determine the foul on the melee line. He stood opposite the sideline referee, and his left and right feet stood on both sides of the line of scrimmage.

Full-court referee-The full-court referee decides the foul of his receiver and linesman. He is also responsible for observing the situation that defenders are blocked by defenders. He judges whether a player is out of bounds. He stood on the same side of the field, 20 yards away from the scuffle line where the game started.

Linesman-linesman decides the foul of his catcher and linesman. He is also responsible for observing the situation that defenders are blocked by defenders. He judges whether a player is out of bounds. He and the linesman stood on the same side of the court, 20 yards away from the line of scrimmage at the beginning of the game.

Backcourt Referee-Backcourt Referee decides to tighten and tighten the player who may block the foul. He is also responsible for timing the 25-second attack clock, timeout and game interruption. He stood 25 yards outside the line of scrimmage.

These referees must remember the rules and decide whether to foul in an instant. The referee threw a yellow flag to signal a foul. There are many rules in the NFL rulebook. Here are some rules you may not know:

Tripping-the blocking behavior of tripping behind the opposing player.

Chopping and blocking-the illegal blocking behavior of throwing the opposing player below the waist. This blocking action has been recognized as causing serious damage to the legs of the opposing players. The team that fouls will be punished to stand back 15 yards.

Infringement-before the attacker touches the ball and starts to attack, the defender invades the neutral zone in advance and contacts with the attacker. The neutral zone is the area separating the offensive and defensive sides before the start of the game, and the distance between the two sides is the length of the ball. The only player who can legally enter the neutral zone is the center, who gives or quickly passes the ball to the quarterback to start the game. Violators will be punished by stepping back five yards.

The audience is too noisy-the referee has the right to decide that the audience is too noisy. The home team may be sent back five yards or lose a timeout.

Legal catch-A player who catches or abandons the ball can show that he doesn't want to fight back by raising his arm in the air. Once he sends a legal signal to catch the ball, the opposing team can't kill him, and he can't leave his position to catch the ball.

Deliberately out of bounds-the quarterback in his own protection circle deliberately throws the ball out of bounds to avoid losing the forward yards because he is caught by the opposing player behind the melee line. When the striker blocks the other quarterback in the game, the encirclement is formed.

Jumping Rule-Although a player can intercept a kicked ball, he can't run behind the melee line 1 yard to intercept it. According to NFL regulations, when an attacker kicks off, defenders within 1 yard of the melee line can jump forward and block the ball. However, if the player's position is more than 1 yard from the line of scrimmage, he can't rush to the line of scrimmage and block the kick-off by jumping and falling down other players. This foul will result in a penalty of 15 yards.

Pleating rules-usually refers to the quarterback and other players dropping the ball when their arms move forward to prepare for passing. This action will be considered as an incomplete pass, not a goal, because his arm is forward.

"Emmett Smith" helmet rule-a player can't take off his helmet on the court unless his protective gear needs to be adjusted. This rule is called "emmett? Smith rule "is because Smith often takes off his helmet to celebrate touchdowns, so he is famous." "The implementation of this regulation is to curb excessive celebration. The player who commits such a foul will be sent back 15 yards.