A man and a woman make an exchange at a yard sale.
Southeby's is running the sale and their sign is visible.
If Southeby's is running a sale a man and woman may not be making an exchange.
exists e1 x1 x2 x3 x4 x5 x6.(Theme(e1,x4) & Actor(e1,x1) & v_make(e1) & at(x4,x5) & n_sale(x5) & of(x5,x6) & n_yard(x6) & n_exchange(x4) & subset_of(x3,x1) & n_woman(x3) & subset_of(x2,x1) & n_man(x2))
exists e1 s1 x1 x2 x3 x4.(n_sign(x4) & of(x4,x3) & n_thing(x3) & n_sale(x3) & Theme(s1,x4) & a_visible(s1) & Theme(e1,x3) & Actor(e1,x1) & v_run(e1) & n_'s(x1) & (x1 = x2) & ne_per_southeby(x2))