Young girls practicing gymnastics.
There children exercising.
Young girls are children and practicing gymnastics is a form of exercising.
exists e1 s1 x1 x2 x3.(a_topic(x1) & Theme(e1,x3) & Actor(e1,x2) & v_practice(e1) & n_gymnastics(x3) & (x1 = x2) & n_girl(x1) & a_young(s1) & Theme(s1,x1))
exists e1 x1.(r_there(e1) & Actor(e1,x1) & v_exercise(e1) & n_child(x1))