Four musicians performing on the street.
A group of people are playing for tourists.
Just because four musicians performing on the street doesn't mean they are playing for tourists.
exists e1 x1 x2 x3.(n_street(x3) & a_topic(x1) & on(e1,x3) & Actor(e1,x2) & v_perform(e1) & (x1 = x2) & n_musician(x1) & card_eq_4(x1))
exists e1 x1 x2 x3.(for(e1,x3) & n_tourist(x3) & Actor(e1,x1) & v_play(e1) & of(x1,x2) & n_people(x2) & n_group(x1))