Three men on horseback rope a calf at a rodeo.
Three men on zebraback
If someone is on horseback, they cannot be on zebraback.
all x1.(n_calf(x1) -> exists x2 x3 x4 x5.(a_topic(x2) & at(x2,x5) & n_rodeo(x5) & for(x2,x1) & on(x2,x3) & n_rope(x3) & of(x3,x4) & n_horseback(x4) & n_man(x2) & card_eq_3(x2)))
exists x1 x2.(a_topic(x1) & on(x1,x2) & n_zebraback(x2) & n_man(x1) & card_eq_3(x1))