Two men are in a Police Rescue boat in the water.
People race their boats.
. People usually refers to more then 2 men.  The first implies they are simply in a boat and the other that they are racing.
exists p1 x1 x5.(n_water(x5) & exists x2 x3 x4.(in(x1,x2) & in(x2,x5) & n_boat(x2) & of(x2,x4) & n_rescue(x4) & of(x2,x3) & n_police(x3)) & n_man(x1) & card_eq_2(x1))
exists s1 s2 x1 x2 x3.(n_boat(x1) & a_their(s2) & Theme(s2,x1) & of(x1,x3) & n_race(x3) & a_.(s1) & Theme(s1,x1) & of(x1,x2) & n_people(x2) & a_topic(x1))