Find the back boundary in doubles
Compare a service landing with a landing after the return, using the same place on the court.
Find two different back lines
With a partner, use an empty standard badminton court marked for singles and doubles. Leave the rackets aside and keep clear of other games. Ask for help identifying the badminton lines if the floor has several sports' markings.
Face the net and find the furthest back boundary. Find the parallel line just in front of it: the doubles long service line. At the sides, doubles uses the outer side lines.
Name the shot before choosing the area
For a service, identify the receiver's diagonally opposite service court: between the short service line and the doubles long service line, and between the centre line and the outer side line on that side.
After the service has been returned, the whole width and length of the opponent's doubles half-court are available. The doubles long service line no longer limits the landing at the back. A boundary line belongs to the area it marks.
Discuss three imaginary landings
Do not hit or throw a shuttle. One person describes each case and points to the imagined first floor contact. The other explains the landing decision. Assume the service otherwise meets the rules and there is no earlier fault.
- Service on the doubles long service line. Choose a place well inside the correct diagonal service court's side limits. This landing is in: the line is included.
- Service behind that line. Keep the same side limits, but move the imagined contact clearly between that line and the back boundary, touching neither. This service landing is out.
- Same place after the return. Imagine a different rally, after a valid service has been returned. A shot landing at the place used in case two is in, within the full doubles court.
Swap roles and explain the same three cases. If an answer differs, check the shot being described before checking the line.
Explain what changed
The floor markings stayed still; the relevant landing area changed. Finish by showing your partner the two back limits and explaining which one applies in each situation.
Judge the first floor contact, not where a shuttle slides afterwards. These examples concern landing areas only: they do not prove that every other part of a service was legal or settle a disputed real rally.
General practice advice: play within your limits and stop if something hurts.