Three people are cooking outside using Two gas grills.
It is for a birthday party
Just because they are cooking outside it does not mean this is for a birthday party.
exists e1 e2 s1 x1 x2 x3.(for(e1,e2) & Theme(e2,x2) & Actor(e2,x1) & v_use(e2) & n_grill(x2) & of(x2,x3) & n_gas(x3) & card_eq_2(x2) & a_outside(s1) & Manner(e1,s1) & Actor(e1,x1) & v_cook(e1) & n_people(x1) & card_eq_3(x1))
exists p1 x1.(n_thing(x1) & exists x2 x3.(for(x1,x2) & n_party(x2) & of(x2,x3) & n_birthday(x3)))