A young boy doing a wheelie on his bike.
A boy crashes his bike.
The boy cannot be doing a wheelie and crashes at once.
exists e1 s1 x1 x2 x3 x4.(a_topic(x1) & Theme(e1,x3) & Actor(e1,x2) & v_do(e1) & on(x3,x4) & n_bike(x4) & of(x4,x1) & n_male(x1) & n_wheelie(x3) & (x1 = x2) & n_boy(x1) & a_young(s1) & Theme(s1,x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_crash(e1) & n_bike(x2) & of(x2,x1) & n_male(x1) & n_boy(x1))