A person is playing a drum.
A person is performing a concert.
Drums can be played for many reasons other than performing a concert.
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_play(e1) & n_drum(x2) & n_person(x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_perform(e1) & n_concert(x2) & n_person(x1))