A boy doing a bike trick is in midair waiting to come back down.
A person is on a bike
The boy in midair is doing a trick on his bike
exists e2 e1 p1 p2 x1 x2 x3 x4.(for(p1,e2) & Topic(e2,p2) & Actor(e2,x1) & v_wait(e2) & exists e3 s1 s2.(a_down(s2) & Manner(e3,s2) & a_back(s1) & Manner(e3,s1) & Actor(e3,x1) & v_come(e3)) & exists x5.(in(x1,x5) & n_midair(x5)) & Theme(e1,x3) & Actor(e1,x2) & v_do(e1) & n_trick(x3) & of(x3,x4) & n_bike(x4) & (x1 = x2) & n_boy(x1))
exists p1 x1.(exists x2.(on(x1,x2) & n_bike(x2)) & n_person(x1))