Question: What makes a homegrown player?

Answer: A homegrown player is a player who, regardless of their nationality or age, has been affiliated with any English or Welsh club for a period of three entire seasons or 36 months before their 21st birthday.

The same rules apply to players who have three seasons or 36 months as a registered player prior to the end of the season in which that player turns 21.

An example of this is Chelsea's Brazilian striker Joao Pedro. The 23-year-old, born in Sao Paulo, joined Watford in January 2020 aged 18.

The regulations differ to Uefa's rules on homegrown players for its competitions. The qualifying period for a player only counts between the ages of 15 and 21, whereas the Premier League's starting age is much younger.

Question: The homegrown rule works the opposite too, right? Eric Dier was not considered a homegrown player in the Spurs squad as he completed his education in Portugal. He is English, played for England and lived in England but was on the books as an overseas player. Mike, Bath

Answer: Correct, Mike. It is all to do with how much time a player has spent effectively doing their football education in England, rather than being about their birthplace.

In the case of Dier, who was listed as a non-homegrown player during his career, he spent less than the three years required at English clubs before turning 21.

A reverse example of this is Noni Madueke, who is homegrown but was at PSV Eindhoven between the ages of 16 and 20 before joining Chelsea. Because Madueke had spent around seven years playing academy football for Crystal Palace and then Tottenham Hotspur prior to moving to Eindhoven, he played enough years of academy football in England to be classed as homegrown.

Question: How does Jeremie Frimpong class as a homegrown player? Daniel, Derby

Answer: Despite being born in Amsterdam and playing internationally for the Netherlands, because Liverpool's Frimpong spent nine years in Manchester City's academy between 2010 and 2019, he is eligible to be a homegrown player.

More information on Premier League squad list rules is available here.

Question: When a player is sold and the agreement includes a sell-on fee for his previous club, how is this fee paid? Does the buying club pay it, or the selling club? And if the transfer is being paid in stages, is the sell-on fee subject to the same procedure? Nick, Brentford

This is how sell-on fees work:

Team A sell a player to Team B for £5m.

Then Team B sell the player to Team C for £20m.

The sell-on fee is usually only applicable to the profit on the transfer, in this case £15m. So a 10% sell-on would be worth £1.5m to Team A.

A sell-on fee is then paid in alignment with the transfer.

So if Team C agreed to pay the £20m fee in four instalments, then Team B would pay the sell-on fee to Team A in four instalments too. Team A will only get paid once Team B have been paid.

This is only a general rule, however. The original contract to sell the player from Team A to Team B could stipulate the sell-on fee should be paid in full.

It is also possible that Team A could ask for the £1.5m immediately, though that usually would involve negotiation and accepting a slightly lower payment.

This article is the latest from BBC Sport's Ask Me Anything team.