I present a complete spectroscopic analysis of a sample of massive (>10^11 M⨀) early-type galaxies (ETGs) in the redshift range 1.41.4 ETGs. Spectroscopic data come from observations obtained with the X-Shooter spectrograph at the VLT which covers with high spectral resolution the spectral bands from the UV to the near IR. The observed wide spectral window allows to perform for each individual target both a full-spectrum fitting analysis to assign the properties of its stellar content (e.g. age, metallicity and abundance ratios), as well as the velocity dispersion estimate. Furthermore, we measure newly explored spectral indices in the UV region (i.e.: MgI, MgII, Mgwide, etc...) in addition to the classical optical Lick/IDS system (i.e.: Hβ, Mgb, etc..), which allow to fix the stellar parameters in a more detailed and complementary way with respect to the global fitting analysis. We compare all the measurements with a large range of stellar population synthesis models, exploring a large parameters space including also non solar values of the chemical abundances. Such a comparison enables us to get hints on the star formation histories of the galaxies sample, in particular on their star formation time-scale within which this passive objects have formed at least the bulk of their stars.