A man is playing guitar by the ocean.
a man performs guitar for his friends at the beach
Playing guitar does not mean his friends are there.
exists e1 x1 x2 x3.(n_ocean(x3) & by(e1,x3) & Theme(e1,x2) & Actor(e1,x1) & v_play(e1) & n_guitar(x2) & n_man(x1))
exists e1 x1 x2 x3 x4.(n_beach(x4) & for(e1,x3) & at(x3,x4) & n_friend(x3) & of(x3,x1) & n_male(x1) & Theme(e1,x2) & Actor(e1,x1) & v_perform(e1) & n_guitar(x2) & n_man(x1))