A man is holding up an exercise ball in the gym.
A man is leading an exercise class.
Just because a  man is holding up an exercise ball in the gym it does not mean he is leading an exercise class.
exists e1 s1 x1 x2 x3 x4.(n_gym(x4) & in(e1,x4) & a_up(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_hold(e1) & n_ball(x2) & of(x2,x3) & n_exercise(x3) & n_man(x1))
exists e1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_lead(e1) & n_class(x2) & of(x2,x3) & n_exercise(x3) & n_man(x1))