guy instructing people in back of train.
A man is giving a safety demonstration in a train.
Guy instructing people in back of train is not necessarily giving a safety demonstration in a train.
exists e1 x1 x2 x3 x4 x5.(a_topic(x1) & in(e1,x4) & of(x4,x5) & n_train(x5) & n_back(x4) & Theme(e1,x3) & Actor(e1,x2) & v_instruct(e1) & n_people(x3) & (x1 = x2) & n_guy(x1))
exists e1 x1 x2 x3 x4.(in(e1,x4) & n_train(x4) & Theme(e1,x2) & Actor(e1,x1) & v_give(e1) & n_demonstration(x2) & of(x2,x3) & n_safety(x3) & n_man(x1))