a group of children playing in a stream
A group of children are playing marco-polo.
Children can play anything on a stream and not necessarily only marco-polo.
exists e1 x1 x2 x3 x4.(a_topic(x1) & of(x1,x2) & in(e1,x4) & n_stream(x4) & Actor(e1,x3) & v_play(e1) & (x2 = x3) & n_child(x2) & n_group(x1))
exists e1 x1 x2 x3.(Theme(e1,x3) & Actor(e1,x1) & v_play(e1) & n_marco-polo(x3) & of(x1,x2) & n_child(x2) & n_group(x1))