A man in a blue shirt is leading children.
a man leads children
man in a blue shirt is leading children  is a rephrasing of  man leads children
exists e1 s1 x1 x2 x3.(Theme(e1,x3) & Actor(e1,x1) & v_lead(e1) & n_child(x3) & in(x1,x2) & n_shirt(x2) & a_blue(s1) & Theme(s1,x2) & n_man(x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_lead(e1) & n_child(x2) & n_man(x1))