The man, the wife and the son are playing together.
Some people are doing something together
They aren't just doing something together, they are playing together.
exists e1 s1 x1 x2 x3 x4 x5.(n_son(x5) & n_wife(x4) & n_man(x2) & a_together(s1) & Manner(e1,s1) & Actor(e1,x1) & v_play(e1) & subset_of(x3,x1) & subset_of(x5,x3) & subset_of(x4,x3) & subset_of(x2,x1))
exists e1 s1 x1 x2.(a_together(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_do(e1) & n_thing(x2) & n_people(x1))