premise: A young barefoot girl wearing a helmet walks down a mossy covered fallen down tree.
hypothesis: A young bicycle rider walks on top of a downed tree for fun.
explanation_1: You can not infer he walks on the tree.
explanation_2: there are reasons other than bicycle riding for people to wear helmets.
explanation_3: Just because the girl is wearing a helmet doesn't mean she was necessarily riding a bicycle.
premise_logic: exists e2 e1 e4 e3 s1 s2 x1 x2 x3 x4 x5 x6 x7 x8.(down(e4,x8) & n_tree(x8) & Actor(e4,x1) & v_fall(e4) & Theme(e3,x4) & Actor(e3,x3) & v_wear(e3) & a_down(s2) & Manner(e2,s2) & Theme(e2,x6) & Actor(e2,x5) & v_walk(e2) & Theme(e1,x7) & v_cover(e1) & (x6 = x7) & n_mossy(x6) & (x4 = x5) & n_helmet(x4) & (x1 = x3) & n_girl(x1) & of(x1,x2) & n_barefoot(x2) & a_young(s1) & Theme(s1,x1))
hypothesis_logic: exists e1 s1 s2 x1 x2 x3 x4 x5.(on(e1,x3) & of(x3,x4) & for(x4,x5) & n_fun(x5) & n_tree(x4) & a_downed(s2) & Theme(s2,x4) & n_top(x3) & Actor(e1,x1) & v_walk(e1) & n_rider(x1) & of(x1,x2) & n_bicycle(x2) & a_young(s1) & Theme(s1,x1))