Workers look on as a tractor is closed off in the street.
A tractor plows a field.
If the tractor is closed off in the street, it cannot be plowing a field.
exists e2 e1 s1 x1 x2 x3 x4.(n_street(x4) & r_on(e1) & as(e1,x2) & in(e2,x4) & a_off(s1) & Manner(e2,s1) & Theme(e2,x3) & v_close(e2) & (x2 = x3) & n_tractor(x2) & Actor(e1,x1) & v_look(e1) & n_worker(x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_plow(e1) & n_field(x2) & n_tractor(x1))