A young woman is leaping in midair on a skateboard.
The woman is young
A young woman could refer to any woman.  The young woman refers to a specific woman.
exists e1 s1 x1 x2 x3.(on(e1,x3) & n_skateboard(x3) & in(e1,x2) & n_midair(x2) & Actor(e1,x1) & v_leap(e1) & n_woman(x1) & a_young(s1) & Theme(s1,x1))
exists s1 x1.(n_woman(x1) & Theme(s1,x1) & a_young(s1))