Synthesis of phenethyl alcohol from benzene
$\ce{AlCl3}$ is a Lewis acid and will bind to the oxygen of the ethylene oxide giving a species that functions as $\ce{[R2O-AlCl2]+}.$ 

This cationic species will be attacked at carbon by the electron-rich aromatic ring in much the same way as a standard Friedel-Crafts reaction intermediate generated from an alkyl halide to give $\ce{[Ph-CH2CH2-OAlCl2]+}.$ This then loses $\ce{HCl}$ to give $\ce{PhCH2CHOAlCl2}$ which is stable until aqueous workup which gives phenethyl alcohol.