premise: A young cowboy is riding bucking bronco in an arena.
hypothesis: A cowboy is swimming in the arena
explanation_1: One can not ride bucking bronco while swimming.
explanation_2: A cowboy does not have to be young.  Riding a bucking bronco means the cowboy is not swimming in the arena.
explanation_3: either the cowboy is riding a bucking bronco or the cowboy is swimming.
premise_logic: exists e1 p1 s1 x1.(exists e2 x2 x3.(in(e2,x3) & n_arena(x3) & Theme(e2,x2) & Actor(e2,x1) & v_buck(e2) & n_bronco(x2)) & Topic(e1,p1) & Actor(e1,x1) & v_ride(e1) & n_cowboy(x1) & a_young(s1) & Theme(s1,x1))
hypothesis_logic: exists e1 x1 x2.(n_arena(x2) & in(e1,x2) & Actor(e1,x1) & v_swim(e1) & n_cowboy(x1))
premise_sim: exists e1 p1 s1 x1.(v_ride(e1) & n_cowboy(x1) & exists e2 x2 x3.(v_buck(e2) & n_bronco(x2) & n_arena(x3) & in(e2,x3) & Theme(e2,x2) & Actor(e2,x1)) & a_young(s1) & Topic(e1,p1) & Theme(s1,x1) & Actor(e1,x1))
hypothesis_sim: exists e1 x1 x2.(v_swim(e1) & n_cowboy(x1) & n_arena(x2) & in(e1,x2) & Actor(e1,x1))