People are waiting in line to order food, while others are walking away with their food.
The people are lined up at a food truck.
Being lined up does not indicate that they are waiting to order - they could be waiting for their orders or simply waiting for service.
exists e1 p1 x1 x2 x3 x4.(exists e2 s1 x5.(with(e2,x3) & a_away(s1) & Manner(e2,s1) & Actor(e2,x5) & v_walk(e2) & -(x5 = x1) & n_person(x5)) & n_food(x3) & n_food(x3) & of(x3,x1) & n_thing(x1) & n_person(x1) & while(e1,p1) & in(e1,x2) & to(x2,x3) & of(x3,x4) & n_order(x4) & n_line(x2) & Actor(e1,x1) & v_wait(e1) & n_people(x1))
exists e1 s1 x1 x2 x3.(n_people(x1) & at(e1,x2) & n_truck(x2) & of(x2,x3) & n_food(x3) & a_up(s1) & Manner(e1,s1) & Theme(e1,x1) & v_line(e1))