Gymnast on bars doing split.
A gymnast is doing a cartwheel.
doing cartwheel and doing split are different kind of activities
exists e1 s1 x1 x2 x3.(ne_nam_gymnast(s1) & a_topic(s1) & on(s1,x1) & Theme(e1,x3) & Actor(e1,x2) & v_do(e1) & n_split(x3) & (x1 = x2) & n_bar(x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_do(e1) & n_cartwheel(x2) & n_gymnast(x1))