Teenagers are looking out the window of a bus.
some boys are running
One can be either looking or running.
exists e1 x1 x2 x3.(n_window(x2) & out(e1,x2) & of(x2,x3) & n_bus(x3) & Actor(e1,x1) & v_look(e1) & n_teenager(x1))
exists e1 x1.(Actor(e1,x1) & v_run(e1) & n_boy(x1))