A person riding a large unicycle.
The man rode the unicycle to win a bet with his friend
There are reasons to ride a unicycle other than because of a bet.
exists e1 s1 x1 x2 x3.(a_topic(x1) & Theme(e1,x3) & Actor(e1,x2) & v_ride(e1) & n_unicycle(x3) & a_large(s1) & Theme(s1,x3) & (x1 = x2) & n_person(x1))
exists e1 p1 x1 x2 x4.(n_friend(x4) & of(x4,x2) & n_male(x2) & n_unicycle(x2) & n_man(x1) & Theme(e1,x2) & Actor(e1,x1) & v_ride(e1) & Topic(x2,p1) & exists e2 x3.(with(e2,x4) & Theme(e2,x3) & Actor(e2,x2) & v_win(e2) & n_bet(x3)))