Keeping this in view we can construct the following paradigm:[…]We thus see that any original simplicity that may have existed in the paradigmata of these words has got thoroughly obscured; and, further that the consonantal stem has often, in one way or another, been changed into a vowel stem, or had a vowel stem substituted for it (cf. Brugmann, Archiv für lateinische Lexicographie u. Grammatik, xv. p. 3 n. 2).