Customers shopping in a food kiosk.
People are shopping.
Customers are people, and shopping in a food kiosk is shopping.
exists x1 x2 x3 x4.(a_topic(x1) & in(x1,x3) & n_kiosk(x3) & of(x3,x4) & n_food(x4) & n_shopping(x1) & of(x1,x2) & n_customer(x2))
exists p1 x1.(exists x2.((x1 = x2) & n_shop(x2)) & n_people(x1))