Items are being sold in the open market by it's vendors.
People are shopping at a small open market.
Not all markets are small and items being sold does not imply people are shopping.
exists e1 p1 s1 x1 x2 x3.(n_thing(x2) & n_market(x2) & a_open(s1) & Theme(s1,x2) & Actor(e1,x2) & exists x4.((x3 = x4) & n_vendor(x4)) & (x2 = x3) & in(e1,x2) & Theme(e1,x1) & v_sell(e1) & n_item(x1))
exists e1 s1 s2 x1 x2.(at(e1,x2) & n_market(x2) & a_open(s2) & Theme(s2,x2) & a_small(s1) & Theme(s1,x2) & Actor(e1,x1) & v_shop(e1) & n_people(x1))