  We use new near-infrared spectroscopy and our published optical spectroscopy
of the gravitationally-lensed Seyfert-2 galaxy F10214+4724 to study both the
links between the starburst and AGN in this object and the properties of the
inner narrow-line clouds. The UV spectrum is consistent with a compact,
moderately- reddened starburst providing about half the UV light. Spectroscopy
of the Halpha /[NII] line blend has enabled us to distinguish emission from the
narrow-line region of the Seyfert-2 and a moderately-reddened emission line
region which we argue is associated with the starburst. Estimates of the star
formation rate from the UV continuum flux and the Halpha flux are broadly
consistent. We can explain the unusual emission line properties of F10214+4724
in terms of conventional models for nearby Seyfert-2 galaxies if lensing is
preferentially magnifying the side of the inner narrow-line region between the
AGN and the observer, and the other side is both less magnified and partially
obscured by the torus. The hydrogen densities of clouds in this region are high
enough to make the Balmer lines optically thick and to suppress forbidden
emission lines with low critical densities. We have deduced the column density
of both ionised and neutral gas in the narrow-line clouds, and the density of
the ionised gas. Using these we have been able to estimate the mass of the
inner narrow-line clouds to be ~ 1 solar mass, and show that the gas:dust ratio
NH/E(B-V) in these clouds must be ~1.3x10^{27}m^{-2}mag^{-1}, significantly
higher than in the Milky Way. The cloud properties are consistent with the
those of the warm absorbers seen in the X-ray spectra of Seyfert-1 galaxies.
Our results favour models in which narrow-line clouds start close to the
nucleus and flow out.
