The system of 16-component equations including two equations of
the Bethe-Salpeter kind (without an interaction) and two
additional conditions are considered. It is shown that the group
of the initial symmetry is $SU(3)_{C}\times SU(2)_{L}\times
U(1)$. The symmetry group is established as the consequence of the
field equations; $ SU(2)$ should be chiral, the color space has
the signature $ (++-)$. The structure of permissible multiplets of
the group coincides with the one postulated in the
$SU(3)_{C}\times SU(2)_{L}$-model of strong and electroweak
interactions excluding the possible existence of the additional $SU(2)_{R}
$-singlet in a generation. It is shown here that at least three puzzling features of the
standard model: the existence of a few generations, the specific
symmetry group, and the necessity to use its interwoven
representations may originate from the composite nature of the
fundamental fermions. \footnote{This paper (in Russian) was deposited in VINITY
19.12.1988 as VINITI No 8842-B88; it was an important stage in the
development of my model of the composite fundamental fermions (see
hep-th/0207210). Now I have translated it in English (small
corrections are made) to do more available.}