Three little girls are sitting on the grass.
There are children sitting in a tree.
Sitting on grass - Sitting in tree - Contradictory
exists e1 s1 x1 x2.(n_grass(x2) & on(e1,x2) & Actor(e1,x1) & v_sit(e1) & n_girl(x1) & a_little(s1) & Theme(s1,x1) & card_eq_3(x1))
exists p1 x1 e1 x2 x3 x4.((x1 = x2) & in(e1,x4) & n_tree(x4) & Actor(e1,x3) & v_sit(e1) & (x2 = x3) & n_child(x2))