The dog walks on the high plank.
A dog is performing a trick.
Just because a dog walks on a high plank does not mean he is performing a trick.
exists e1 s1 x1 x2.(n_plank(x2) & a_high(s1) & Theme(s1,x2) & n_dog(x1) & on(e1,x2) & Actor(e1,x1) & v_walk(e1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_perform(e1) & n_trick(x2) & n_dog(x1))