  Context. This research paper contains light curve modelling, spectroscopy and
detailed asteroseismic studies for four out of five in total semidetached
eclipsing binaries with a delta Scuti component, that have been detected to
date through Kepler mission, namely KIC 06669809, KIC 10581918, KIC 10619109
and KIC 11175495.
  Aims. The goal is to study the pulsational characteristics of the oscillating
stars of the systems as well as to estimate their absolute parameters and
enrich the so far poor sample of this kind of systems.
  Methods. Ground based spectroscopic observations provide the means to
estimate the spectral types of the primary components and to model the light
curves with higher certainty. The photometric data are analysed using eclipsing
binary modeling techniques, while Fourier analysis is applied on their
residuals in order to reveal the pulsation frequency modes.
  Results. The results of analyses show that the primaries are pulsating stars
of delta Scuti type and that all systems belong to the group of Algol type
binaries with an oscillating star, namely oEA stars. The primaries of KIC
06669809, KIC 10581918, and KIC 10619109 pulsate in three, two, and five
frequencies, respectively and in more than 200 other detected as combinations.
The delta Scuti star of KIC 11175495 is the youngest and the fastest pulsator
in binary systems that has ever been found and it oscillates in three main non
radial frequencies, while other 153 are also found as depended ones. Moreover,
a comparison of their properties with other systems of the same type as well as
with theoretical models of pulsating stars are also presented and discussed.
