A boy in a blue jacket on a subway train.
A boy on a train.
The type of train is a subway train.
exists s1 x1 x2 x3 x4.(a_topic(x1) & in(x1,x2) & on(x2,x3) & n_train(x3) & of(x3,x4) & n_subway(x4) & n_jacket(x2) & a_blue(s1) & Theme(s1,x2) & n_boy(x1))
exists x1 x2.(a_topic(x1) & on(x1,x2) & n_train(x2) & n_boy(x1))