Three male and female pairs of dancers are on the stage at the ballet, with other ballerinas in the background.
Some dancers are on stage with others behind them.
"Some" is a less specific term for "three male and female pairs". If ballerinas are behind them then "others" are behind them.
exists p1 s1 x1 x2 x3 x4 x5 x6 x7 x8.(n_background(x7) & n_ballerina(x6) & n_ballet(x4) & n_stage(x8) & with(p1,x5) & in(x5,x7) & -(x5 = x6) & n_ballerina(x5) & at(p1,x4) & on(x1,x8) & of(x1,x3) & n_dancer(x3) & n_pair(x1) & a_female(s1) & Theme(s1,x1) & of(x1,x2) & n_male(x2) & card_eq_3(x1))
exists p1 x1.(behind(p1,x1) & n_thing(x1) & exists x2 x3.(on(x1,x2) & with(x2,x3) & -(x3 = x1) & n_person(x3) & n_stage(x2)) & n_person(x1) & n_dancer(x1))