People sitting together while one of them is taking pictures.
A person takes pictures while sitting.
One person is taking pictures while sitting with someone else.
exists e1 p1 p2 x1 x2.(a_topic(x1) & exists e2 x3 x4.(Theme(e2,x4) & Actor(e2,x3) & v_take(e2) & n_picture(x4) & of(x3,x1) & n_thing(x3) & card_eq_1(x3)) & n_thing(x1) & while(e1,p2) & exists s1.(Theme(s1,x2) & a_together(s1)) & Topic(e1,p1) & Actor(e1,x2) & v_sit(e1) & (x1 = x2) & n_people(x1))
exists e2 e1 x1 x2.(while(e1,e2) & Actor(e2,x1) & v_sit(e2) & Theme(e1,x2) & Actor(e1,x1) & v_take(e1) & n_picture(x2) & n_person(x1))