A man pushes a miniature train engine which a little boy, possibly his son, is riding down a track at a park of some sort.
Someone is pushes a train and people are watching.
Pushing a little boy, whether or not it is your son, does not imply that people are watching.
exists e1 p1 x1 x2 x3 x4 x6.(Theme(e1,x2) & Actor(e1,x1) & v_push(e1) & exists e2 s1 s2 x5 x7 x8 x9.(at(e2,x8) & of(x8,x9) & n_sort(x9) & n_park(x8) & a_down(s2) & Manner(e2,s2) & Theme(e2,x7) & Actor(e2,x5) & v_ride(e2) & n_track(x7) & rel(x5,x6) & r_possibly(x6) & n_boy(x5) & a_little(s1) & Theme(s1,x5)) & n_son(x6) & of(x6,x1) & n_male(x1) & which(x2,p1) & n_engine(x2) & of(x2,x4) & n_train(x4) & of(x2,x3) & n_miniature(x3) & n_man(x1))
exists p1 x1.(exists e1 x2 x3 x4 x5 x6.((x1 = x2) & Theme(e1,x6) & Actor(e1,x3) & v_watch(e1) & (x2 = x6) & subset_of(x5,x3) & n_people(x5) & subset_of(x4,x3) & n_train(x4) & n_push(x2)) & n_person(x1))