We consider the pion structure in the region of low and moderately high momentum transfers: at low $Q^2$, the pion is treated as a composite system of constituent quarks; at moderately high momentum transfers, $Q^2=10div25;GeV^2$, the pion ff is calculated within perturbative QCD taking into account one--gluon hard exchange. Using the data on pion ff at $Q^2<3;GeV^2$ and pion axial--vector decay constant, we reconstruct the pion wf in the soft and intermediate regions. This very wave function combined with one--gluon hard scattering amplitude allows a calculation of the pion ff in the hard region $Q^2=10div25;GeV^2$. A specific feature of the reconstructed pion wf is a quasi--zone character of the $qbar q$--excitations. On the basis of the obtained pion wf and the data on deep inelastic scattering off the pion, the valence quark distribution in a constituent quark is determined.
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