A street vendor with a green apron smiles behind his food cart.
A vendor is frowning.
One cannot be frowning and smiling at the same time
exists e1 s1 x1 x2 x3 x4 x5.(behind(e1,x4) & n_cart(x4) & of(x4,x5) & n_food(x5) & of(x4,x1) & n_male(x1) & Actor(e1,x1) & v_smile(e1) & with(x1,x3) & n_apron(x3) & a_green(s1) & Theme(s1,x3) & n_vendor(x1) & of(x1,x2) & n_street(x2))
exists e1 x1.(Actor(e1,x1) & v_frown(e1) & n_vendor(x1))