a baby wears a Santa hat.
The baby is smiling.
A baby does not always smiling.
exists e1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_wear(e1) & n_hat(x2) & (x2 = x3) & ne_org_santa(x3) & n_baby(x1))
exists e1 x1.(n_baby(x1) & Actor(e1,x1) & v_smile(e1))