A man surrounded by others in a subway train.
The man knows someone on the subway train.
Just because a man is surrounded by others on a subway doesn't mean he knows someone on the subway
exists e1 x1 x2 x3 x4 x5.(a_topic(x1) & in(e1,x4) & n_train(x4) & of(x4,x5) & n_subway(x5) & Actor(e1,x3) & -(x3 = x1) & n_person(x1) & n_person(x3) & Theme(e1,x2) & v_surround(e1) & (x1 = x2) & n_man(x1))
exists e1 x1 x2 x3 x4.(n_train(x3) & of(x3,x4) & n_subway(x4) & n_man(x1) & Theme(e1,x2) & Actor(e1,x1) & v_know(e1) & on(x2,x3) & n_person(x2))