These people are sitting outside on a sunny day.
People are sitting together in a group, eating a picnic lunch.
Sitting outside does not imply eating a picnic lunch.
exists e1 s1 s2 x1 x2.(n_people(x1) & on(e1,x2) & n_day(x2) & a_sunny(s2) & Theme(s2,x2) & a_outside(s1) & Manner(e1,s1) & Actor(e1,x1) & v_sit(e1))
exists e1 e2 p1 x1 x2 x3 x4.(for(e1,e2) & Theme(e2,x3) & Actor(e2,x1) & v_eat(e2) & n_lunch(x3) & of(x3,x4) & n_picnic(x4) & in(e1,x2) & n_group(x2) & exists s1.(Theme(s1,x1) & a_together(s1)) & Topic(e1,p1) & Actor(e1,x1) & v_sit(e1) & n_people(x1))