A multiple gate dielectrics and dual work-functions field effect transistor (MGO-DWF-FET) is provided on an active region of a semiconductor substrate. The MGO-DWF-FET includes a first functional gate structure including a U-shaped first high-k gate dielectric material layer and a first work-function metal-containing structure, and a laterally adjacent, and contacting, second functional gate structure that includes a U-shaped second high-k gate dielectric material layer and a second work-function metal-containing structure. The first functional gate structure has a gate length that differs from a gate length of the second functional gate structure.