Two martial artists practice in a vacant room.
Two ballet dancers practice in a vacant room
Martial artists are not the same as ballet dancers.
exists s1 s2 x1 x2 x3.(a_topic(x1) & in(x1,x3) & n_room(x3) & a_vacant(s2) & Theme(s2,x3) & n_practice(x1) & of(x1,x2) & n_artist(x2) & a_martial(s1) & Theme(s1,x1) & card_eq_2(x1))
exists s1 x1 x2 x3 x4.(a_topic(x1) & in(x1,x4) & n_room(x4) & a_vacant(s1) & Theme(s1,x4) & n_practice(x1) & of(x1,x3) & n_dancer(x3) & of(x1,x2) & n_ballet(x2) & card_eq_2(x1))