a kayaker tumbles over.
A person on a kayak tumbles over.
If a kayak tumbles over, the person on the kayak also tumbles over.
exists e1 s1 x1.(a_over(s1) & Manner(e1,s1) & Actor(e1,x1) & v_tumble(e1) & n_kayaker(x1))
exists e1 s1 x1 x2.(a_over(s1) & Manner(e1,s1) & Actor(e1,x1) & v_tumble(e1) & on(x1,x2) & n_kayak(x2) & n_person(x1))