Four people are jumping from the top of a flight of stairs.
The people are testing their athletic skills.
Jumping does not imply testing athletic skills.
exists e1 x1 x2 x3 x4.(n_top(x2) & from(e1,x2) & of(x2,x3) & of(x3,x4) & n_stair(x4) & n_flight(x3) & Actor(e1,x1) & v_jump(e1) & n_people(x1) & card_eq_4(x1))
exists e1 s1 x1 x2.(n_skill(x2) & a_athletic(s1) & Theme(s1,x2) & of(x2,x1) & n_thing(x1) & n_people(x1) & Theme(e1,x2) & Actor(e1,x1) & v_test(e1))