How does the polarised dielectric modify the original external field inside it?

(N/A) When a dielectric is placed in an external electric field $\overrightarrow{E}_{0}$,the molecules (polar or non-polar) align themselves,resulting in a net dipole moment per unit volume,which is called polarisation $\overrightarrow{P}$.
This polarisation creates an internal induced electric field $\overrightarrow{E}_{p}$ that opposes the external field $\overrightarrow{E}_{0}$.
The net electric field $\overrightarrow{E}$ inside the dielectric is given by the vector sum of the external field and the induced field:
$\overrightarrow{E} = \overrightarrow{E}_{0} + \overrightarrow{E}_{p}$
Since $\overrightarrow{E}_{p}$ is in the opposite direction to $\overrightarrow{E}_{0}$,the magnitude of the net electric field inside the dielectric is reduced:
$E = E_{0} - E_{p}$
Thus,the polarised dielectric reduces the original external field inside it.