A person on a bmx bike.
A cyclist who just got a BMX bike for their birthday
Not every person on a bike just received it for their birthday.
exists x1 x2 x3.(a_topic(x1) & on(x1,x2) & n_bike(x2) & of(x2,x3) & n_bmx(x3) & n_person(x1))
exists e1 s1 x1 x2 x3 x4 x5.(a_topic(x1) & a_just(s1) & Manner(e1,s1) & Theme(e1,x3) & Actor(e1,x2) & v_get(e1) & for(x3,x5) & n_birthday(x5) & of(x5,x1) & n_thing(x1) & n_bike(x3) & (x3 = x4) & ne_org_bmx(x4) & (x1 = x2) & n_cyclist(x1))