A woman is swimming underwater.
A lady is swimming.
A woman is a lady.
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_swim(e1) & n_underwater(x2) & n_woman(x1))
exists p1 x1.(exists x2.((x1 = x2) & n_swimming(x2)) & n_lady(x1))