  Recently a nice work about the understanding of one-loop integrals has been
done in [1] using the tricks of the projective space language associated to
their Feynman parametrization. We find this language is also very suitable to
deal with the reduction problem of one-loop integrals with general tensor
structures as well as propagators with arbitrary higher powers. In this paper,
we show that how to combine Feynman parametrization and embedding formalism to
give a universal treatment of reductions for general one-loop integrals, even
including the degenerated cases, such as the vanishing Gram determinant.
Results from this method can be written in a compact and symmetric form.
