a man walking the streets while playing the guitar.
An elephant stamps its foot.
The subject is either a man who is walking or an elephant who is stamping.
exists e2 e1 x1 x2 x3 x4.(n_guitar(x4) & n_street(x3) & a_topic(x1) & while(e1,e2) & Theme(e2,x4) & Actor(e2,x2) & v_play(e2) & Theme(e1,x3) & Actor(e1,x2) & v_walk(e1) & (x1 = x2) & n_man(x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_stamp(e1) & n_foot(x2) & of(x2,x1) & n_thing(x1) & n_elephant(x1))