This is a railroad engineer working on a green and red tourism train in a theme park.
An engineer is working on a train engine.
the fact that the engineer is working on a train does not imply that the part of the train being worked on is the engine.
exists p1 x1.(n_thing(x1) & exists e1 s1 s2 x2 x3 x4 x5 x6 x7 x8.((x1 = x2) & in(e1,x7) & n_park(x7) & of(x7,x8) & n_theme(x8) & on(e1,x5) & n_train(x5) & of(x5,x6) & n_tourism(x6) & a_red(s2) & Theme(s2,x5) & a_green(s1) & Theme(s1,x5) & Actor(e1,x4) & v_work(e1) & (x2 = x4) & n_engineer(x2) & of(x2,x3) & n_railroad(x3)))
exists e1 x1 x2 x3.(on(e1,x2) & n_engine(x2) & of(x2,x3) & n_train(x3) & Actor(e1,x1) & v_work(e1) & n_engineer(x1))