This is a group of children playing Wii.
A group of boys and girls are playing Wii.
A group of children is not necessary to be a group of boys and girls. They can be group of boys or girls only.
exists p1 x1 x5.(ne_geo_wii(x5) & n_thing(x1) & exists e1 x2 x3 x4.((x1 = x2) & of(x2,x3) & Theme(e1,x5) & Actor(e1,x4) & v_play(e1) & (x3 = x4) & n_child(x3) & n_group(x2)))
exists e1 x1 x2 x3 x4 x5.(ne_geo_wii(x5) & Theme(e1,x5) & Actor(e1,x1) & v_play(e1) & of(x1,x2) & subset_of(x4,x2) & n_girl(x4) & subset_of(x3,x2) & n_boy(x3) & n_group(x1))