The lady is sitting at the sewing machine working.
The lady is working at her sewing machine.
sitting at the sewing machine working almost the same as working at her sewing machine
exists e2 e1 s1 x1 x2 x3.(n_machine(x2) & Actor(e2,x2) & v_sew(e2) & n_lady(x1) & at(e1,x2) & Theme(s1,x3) & a_working(s1) & (x2 = x3) & Actor(e1,x1) & v_sit(e1))
exists e1 x1 x2 x3.(n_machine(x2) & of(x2,x3) & n_sewing(x3) & of(x2,x1) & n_female(x1) & n_lady(x1) & at(e1,x2) & Actor(e1,x1) & v_work(e1))