A man standing by a train holding a bird.
a man throws a bird in front of the train
the man standing by train with a bird does not imply he throws it i front of the train
exists e1 x1 x2 x3 x4 x5.(a_topic(x1) & by(x1,x3) & Theme(e1,x5) & Actor(e1,x4) & v_hold(e1) & n_bird(x5) & (x3 = x4) & n_train(x3) & n_standing(x1) & of(x1,x2) & n_man(x2))
exists e1 x1 x2 x3 x4.(n_train(x4) & in(e1,x3) & of(x3,x4) & n_front(x3) & Theme(e1,x2) & Actor(e1,x1) & v_throw(e1) & n_bird(x2) & n_man(x1))