A woman and boy sit on a police motorcycle.
A woman a boy pose as a motorcycle passes by.
People cannot be sitting on a motorcycle if the bike passes by
exists e1 x1 x2 x3 x4 x5.(on(e1,x4) & n_motorcycle(x4) & of(x4,x5) & n_police(x5) & Actor(e1,x1) & v_sit(e1) & n_boy(x3) & n_woman(x2) & subset_of(x3,x1) & subset_of(x2,x1))
all x1.(n_boy(x1) -> exists e1 p1 x2.(exists e2 s1 x3.(a_by(s1) & Manner(e2,s1) & Actor(e2,x3) & v_pass(e2) & n_motorcycle(x3)) & as(e1,p1) & Actor(e1,x2) & v_pose(e1) & for(x2,x1) & n_woman(x2)))