Ethylbenzene is generally prepared by acetylation of benzene followed by reduction and not by the direct alkylation of benzene. Think of a possible reason.

Explanation

Benzene ring has been deactivated due to resonance. It is not in a position to generate the electrophile from the attacking reagent i.e., ethyl halide `(C_(2)H_(5)-X)` so easily. Now, acetyl chloride `(CH_(3)COCl)` can release the electrophile more readily since the carbonyl group is an electron withdrawing group. The cleavage of C-Cl bond is quite easy in this case.