  In the heavy-quark limit, the decay spectrum for radiative and semileptonic
inclusive B-meson decays is determined by a universal structure function, i.e.
the shape function. We study the constraints on the bilocal heavy-quark
operator for the shape function from the QCD equations of motion and
heavy-quark symmetry, and we obtain a new basis of nonlocal operators that
reveals relevant soft components in the shape function. Those nonlocal
operators represent the ``kinetic energy distribution'' of the b-quark inside
the B-meson and the four-parton correlations with additional quarks and gluons.
A corresponding local operator basis relevant for relating the shape function
to HQET parameters is also given, and novel effects of the quark-gluon
correlations are discussed.
