A boy in black clothes is doing a cartwheel on the beach.
A girl plays on the beach.
One can be a boy or a girl, not both simultaneously.
exists e1 s1 x1 x2 x3 x4.(n_beach(x4) & Theme(e1,x3) & Actor(e1,x1) & v_do(e1) & on(x3,x4) & n_cartwheel(x3) & in(x1,x2) & n_clothes(x2) & a_black(s1) & Theme(s1,x2) & n_boy(x1))
exists e1 x1 x2.(n_beach(x2) & on(e1,x2) & Actor(e1,x1) & v_play(e1) & n_girl(x1))