A child in a fuzzy blue hat on a tricycle.
the kid was on a tricycle for the first time
On a tricycle does not imply that it is the first time.
exists s1 s2 x1 x2 x3.(a_topic(x1) & in(x1,x2) & on(x2,x3) & n_tricycle(x3) & n_hat(x2) & a_blue(s2) & Theme(s2,x2) & a_fuzzy(s1) & Theme(s1,x2) & n_child(x1))
exists p1 s1 x1 x2.(n_time(x2) & a_first(s1) & Theme(s1,x2) & n_kid(x1) & for(p1,x2) & exists x3.(on(x1,x3) & n_tricycle(x3)))