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We introduce and study the properties of the "color-straight" four-quarkoperators containing heavy and light quark fields. They are of the form (\barb\Gamma_b b)(\bar q\Gamma_q q) where both brackets are color singlets. Theirexpectation values include the bulk of the nonfactorizable contributions to thenonleptonic decay widths of heavy hadrons. The expectation values of thecolor-straight operators in the heavy hadrons are related to the momentumintegrals of the elastic light-quark formfactors of the respective heavyhadron. We calculate the asymptotic behavior of the light-current formfactorsof heavy hadrons and show that the actual decrease is 1/(q^2)^3/2 rather than1/q^4. The two-loop hybrid anomalous dimensions of the four-quark operators andtheir mixing (absent in the first loop) are obtained. Using plausible modelsfor the elastic formfactors, we estimate the expectation values of thecolor-straight operators in the heavy mesons and baryons. Improved estimateswill be possible in the future with new data on the radiative decays of heavyhadrons. We give the Wilson coefficients of the four-fermion operators in the1/m_b expansion of the inclusive widths and discuss the numerical predictions.Estimates of the nonfactorizable expectation values are given.Comment: 51 pages. The case of flavor-singlet operators is added for the  two-loop anomalous dimension

Four-fermion heavy quark operators and light current amplitudes in heavy flavor hadrons