The man and woman are sitting by the boats.
A couple hold hands beside some boats
Not every man and woman is a couple. There is no indication the man and woman are holding hands.
exists e1 x1 x2 x3 x4.(n_boat(x4) & n_woman(x3) & n_man(x2) & subset_of(x3,x1) & subset_of(x2,x1) & by(e1,x4) & Actor(e1,x1) & v_sit(e1))
exists e1 x1 x2 x3 x4 x5.(beside(e1,x5) & n_boat(x5) & rel(e1,x4) & n_hand(x4) & Theme(e1,x2) & Actor(e1,x1) & v_event(e1) & n_hold(x2) & of(x2,x3) & n_couple(x3) & n_thing(x1))