Four boys play in the mud.
Four boys are sitting at a table.
The four boys ca not be sitting at a table and playing in mud at the same time.
exists x1 x2 x3.(n_mud(x3) & a_topic(x1) & in(x1,x3) & n_play(x1) & of(x1,x2) & n_boy(x2) & card_eq_4(x1))
exists e1 x1 x2.(at(e1,x2) & n_table(x2) & Actor(e1,x1) & v_sit(e1) & n_boy(x1) & card_eq_4(x1))