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Super Bowl 51: A beginner's guide to American football

New England Patriots quarterback Tom Brady celebrates with the Vince Lombardi Trophy after the NFL Super Bowl XLIX football game against the Seattle SeahawksAP
The Super Bowl winners get to lift the Vince Lombardi trophy

Some call it the greatest sporting event in the world. Others tune in for the half-time entertainment or to spot A-list celebrities in the crowd.

Whatever the reason, more than 150 million people worldwide are expected to watch the New England Patriots take on the Atlanta Falcons in Super Bowl 51 on Sunday night in Houston, Texas. The big game kicks off at 11.30pm with Lady Gaga performing in the half-time show.

If you don't know much about the sport but want to know more then don't worry.

Here are some handy phrases so you can sound just like an expert. Let's start with the basics.

Offence and Defence

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Each team is split into two units; an attacking one and a defensive one.

The team which has control of the ball will have their offence (attacking players) on the pitch. The attacking players will attempt to move the ball forward and score touchdowns.

Atlanta Falcons wide receiver Julio Jones (11) scores a touchdown ahead of Green Bay Packers cornerback LaDarius Gunter (36) during the second quarter in the 2017 NFC Championship Game at the Georgia Dome.Reuters
The offence will try to get the football to the end zone for a touchdown. The opposing side's defence will try to stop that from happening

The team without it will have their defence (defensive players) on. The role of the defence is to stop the other team from scoring by tackling the ball-carrier, intercepting passes or causing fumbles.

This is true for most of the game except when one team has chosen to kick the ball. The 'special teams' come on for that.

Top tip: Make sure you pronounce defence like this: "Dee-fence".

Examples you could use: "New England's offence relies a lot on Tom Brady to be successful don't you think?" or "Atlanta's defence is the best in the National Football League".

1st, 2nd, 3rd and 4th Down

New England Patriots wide receiver Chris Hogan (15) catches a pass for a touchdown against Los Angeles Rams cornerback E.J. Gaines (33) during the first half of an NFL football game, Sunday, Dec. 4, 2016AP
Teams often run with the ball on 1st Down

These 'downs' are key to the game and will pop up all the time, so nail these and you'll sound like a pro!

Basically you get four attempts (a down) to move the ball 10 yards (by either running or passing it).

If you make 10 yards then you get another set of four downs.

If you have ever watched American football before you might have seen the words '1st and 10' written in the corner of your TV screen. That means it's the 1st Down with 10 yards to make.

If a team makes three yards, for example, then next it's 2nd and Seven, 3rd and Four etc. If they fail to make 10 yards in the four downs then the other team gets the ball.

Top tip: If teams fail to make 10 yards on their first three attempts then they'll probably kick it away on their 4th down. This means the other team will have further to go to score.

Examples of use: "I'd throw the ball deep on Second down" or "Atlanta always run the ball on First down"

The Quarterback

Matt RyanAP
Matt Ryan will try to win his first Super Bowl with the Atlanta Falcons on Sunday

A quarterback is the leader of the team and the player that throws the ball a lot. On Sunday two of the best in the business will be playing.

Atlanta Falcons are led by Matt Ryan, who has had a brilliant season so far in which he has thrown for 38 touchdowns.

Matty Ice, as he is known by fans, has also formed a devastating partnership with speedy receiver Julio Jones.

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The play-maker for New England is the legendary Tom Brady, who has won the Super Bowl four times already with New England.

The 39-year-old has come back after being suspended for four games at the start of the season for his alleged involvement in 2015's 'deflate-gate' scandal.

Brady is a more of a traditional player, called a "pocket passer". He will tend to stand in one spot and throw the ball.

Top tip: Players like Tom Brady have kept the traditional way of playing the position alive. Some had predicted that pocket passers would become a thing of the past.

Examples of use: "I think Tom is a good example of how pocket passers can still be successful in the league."

Scoring

Atlanta Falcons wide receiver Justin Hardy (16) makes a touchdown catch against New Orleans Saints cornerback Sterling Moore (24) during the first half of an NFL football game, Sunday, Jan. 1, 2017, in Atlanta.AP
The aim for any American football team is to score touchdowns by taking the ball into the end zone

Touchdown (six points) - A touchdown is scored when a team crosses the opposition's goal line with the ball, or catches or collects the ball in the end zone.

Field goal (three points) - These are usually attempted on fourth down if the kicker is close enough to the end zone to kick the ball through the posts, or uprights.

Extra point (one or two points) - A point is earned by kicking the ball through the uprights after a touchdown (similar to a rugby conversion). Two points are earned by taking the ball into the end zone again.

Safety (two points) - Awarded to the defensive team when a member of the offensive team is tackled with the ball in his own end zone.