A girl is performing a wheelie on her bicycle in front of a gray cinder block building.
A boy is skateboarding.
The subject cannot be a boy and a girl at the same time.
exists e1 s1 x1 x2 x3 x4 x5 x6 x7.(in(e1,x4) & of(x4,x5) & n_building(x5) & of(x5,x7) & n_block(x7) & of(x5,x6) & n_cinder(x6) & a_gray(s1) & Theme(s1,x5) & n_front(x4) & on(e1,x3) & n_bicycle(x3) & of(x3,x1) & n_female(x1) & Theme(e1,x2) & Actor(e1,x1) & v_perform(e1) & n_wheelie(x2) & n_girl(x1))
exists e1 x1.(Actor(e1,x1) & v_skateboard(e1) & n_boy(x1))