Items are being sold in the open market by it's vendors.
Vendors are preventing people from buying their items
Vendors cannot be preventing people from buying items while items are being sold.
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 e2 e1 x1 x2 x3 x4.(from(e1,e2) & Theme(e2,x4) & Actor(e2,x3) & v_buy(e2) & n_item(x4) & of(x4,x1) & n_thing(x1) & Theme(e1,x2) & Actor(e1,x1) & v_prevent(e1) & n_people(x2) & n_vendor(x1))