People watch a musician play the guitar.
People are listening to rock music.
A musician can play more than only rock music on a guitar.
exists e1 s1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_watch(e1) & n_guitar(x3) & (x2 = x3) & n_play(x2) & a_musician(s1) & Theme(s1,x2) & n_people(x1))
exists e1 p1 x1.(Topic(e1,p1) & Actor(e1,x1) & v_listen(e1) & exists e2 x2.(Theme(e2,x2) & Actor(e2,x1) & v_rock(e2) & n_music(x2)) & n_people(x1))