Two boys wearing life jackets on a boat.
Two people wearing life jackets on a boat.
boys are people, therefore the word people can be used in place of boys.
exists e1 x1 x2 x3 x4.(a_topic(x1) & on(x1,x4) & n_boat(x4) & n_jacket(x1) & of(x1,x3) & n_life(x3) & Actor(e1,x1) & v_wear(e1) & of(x1,x2) & n_boy(x2) & card_eq_2(x1))
exists e1 x1 x2 x3 x4 x5.(a_topic(x1) & Theme(e1,x3) & Actor(e1,x2) & v_wear(e1) & on(x3,x5) & n_boat(x5) & n_jacket(x3) & of(x3,x4) & n_life(x4) & (x1 = x2) & n_people(x1) & card_eq_2(x1))