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We discuss vector, axial-vector, scalar and pseudoscalar two-point functionsat low and intermediate energies. We first review what is known from chiralperturbation theory, as well as from a heat kernel expansion within the contextof the extended Nambu-Jona-Lasinio (ENJL) model of ref. \cite{12}. In this workwe derive then these two-point functions to all orders in the momenta and toleading order in $1/N_c$. We find an improved high-energy behaviour and ageneral way of parametrizing them that shows relations between some of thetwo-point functions, which are also valid in the presence of gluonicinteractions. The similarity between the shape of the experimentally knownspectral functions and the ones we derive, is greatly improved with respect tothose predicted by the usual constituent quark like models. We also obtain thescalar mass $M_S = 2 M_Q$ independent of the regularization scheme. In the end,we calculate fully an example of a nonleptonic matrix element in theENJL--model, the $\pi^+-\pi^0$ electromagnetic mass difference and find goodagreement with the measured value.Comment: 37 pages + 6 uuencoded figures, CERN TH 6924/93, CPT-93/P.2917,  NORDITA 93/43-N,

Low-energy behaviour of two-point functions of quark currents