A woman is riding her bicycle.
The woman is not walking.
If a woman is riding her bicycle she is not walking.
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_ride(e1) & n_bicycle(x2) & of(x2,x1) & n_female(x1) & n_woman(x1))
exists x1.(n_woman(x1) & -exists e1.(Actor(e1,x1) & v_walk(e1)))