"The ___ of G.I. Joe," 1945 film starring Burgess Meredith, now preserved in the National Film Registry

Take unfair advantage of, say3 Large coffee container3 Bring a civil action against, say3 Three-in-one doctor: Abbr.3 Pat lightly, with a napkin3 "Well, lah-di-___!"3 Curly-tailed Japanese dog5 Fundamental or elementary, as a concept5