A person with a skateboard is sitting on a bench.
The skater is doing a trick.
Sitting on a bench and doing a trick can not be done simultaneously by the person.
exists e1 x1 x2 x3.(on(e1,x3) & n_bench(x3) & Actor(e1,x1) & v_sit(e1) & with(x1,x2) & n_skateboard(x2) & n_person(x1))
exists e1 x1 x2.(n_skater(x1) & Theme(e1,x2) & Actor(e1,x1) & v_do(e1) & n_trick(x2))