  In the context of the Standard Model we show how to apply the pinch technique
to four-fermion amplitudes with non-conserved external charged currents,in
order to construct to one-loop order gauge independent self-energies and
vertices. We discuss the technical difficulties arising due to the presence of
longitudinal contributions from the W and Goldstone boson ($\phi$) propagators,
and derive gauge independent $WW$, $\phi W$, and $\phi\phi$ effective
self-energies, and vertices. The quantities so constructed satisfy a set of
Ward identities, whose validity enforces the gauge invariance of the physical
amplitude considered; their derivation does not require knowledge of the
explicit closed form of the gauge independent self-energies and vertices. Use
of these Ward identities enables the decomposition of the amplitude in
manifestly gauge independent transverse and longitudinal structures with
distinct kinematic properties. Explicit one-loop calculations are carried out,
and several applications of the results are briefly discussed.}
