Two guys having fun playing and singing a song.
The guys here are actively interacting with each other.
Interacting can be playing and singing a song.   Two guys having fun are interacting with each other.
exists e1 e2 x1 x2 x3 x4 x5.(Theme(e2,x5) & Actor(e2,x4) & v_sing(e2) & n_song(x5) & n_guy(x4) & card_eq_2(x4) & Theme(e1,x2) & Actor(e1,x1) & v_have(e1) & n_playing(x2) & of(x2,x3) & n_fun(x3) & n_guy(x1) & card_eq_2(x1))
exists e1 s1 x1.(n_guy(x1) & a_actively(s1) & Manner(e1,s1) & all x2.(n_other(x2) -> with(e1,x2)) & Actor(e1,x1) & v_interact(e1) & r_here(x1))