A woman wearing headphones walks down the street.
A woman walking down the street.
The second sentence implies that the imprtance of the previous sentence was that the woman was walking, rather than the fact that she was wearing headphones.
exists e1 e2 x1 x2 x3 x4.(n_street(x4) & down(e2,x4) & Actor(e2,x1) & v_walk(e2) & Theme(e1,x3) & Actor(e1,x2) & v_wear(e1) & n_headphone(x3) & (x1 = x2) & n_woman(x1))
exists e1 s1 x1 x2 x3.(n_street(x3) & a_topic(x1) & a_down(s1) & Manner(e1,s1) & Theme(e1,x3) & Actor(e1,x2) & v_walk(e1) & (x1 = x2) & n_woman(x1))