 Dancers are paired-up into male-female couples that will sometimes stay paired for much of the remaining competition if neither is eliminated (since season 7, competitors have also been occasionally paired with "All Stars", returning dancers from previous seasons who partner with the contestant dancers, but who are not themselves competing).These couples perform 1–2 duets per week in different styles which are typically, but not always, randomly selected.These duets, as with all non-solo performances at this stage in the competition, are choreographed by professional choreographers.