157. Differences in accentuation and in the environment of vowels or consonants regularly developed different stems in different parts of some verbs. For instance, ádjūtā́re ＞ aidar (§ [45]), while adjū́tat ＞ aiüda.
158. Sometimes, as above, an intertonic vowel disappeared: mándūcā́re ＞ maniar, mandūco ＞ ✱mandüc manüc; ✱parabolāre ✱páraulā́re ＞ parlar, ✱parabŏlat ✱paraulat ＞ paraula. In such cases the shortened stem usually prevailed: mania, parla. But in adjutare the longer one was preferred: aiüdar.
159. (1) A vowel which breaks in one part of a verb may be unstressed, and therefore remain unbroken, in another part: probāre ＞ proar, prŏbat ＞ prueva,[116] ✱sequīre ＞ sęguir, ✱sĕquit ＞ sięc.[117] In such cases the phonetic development is generally undisturbed.
(2) A vowel which breaks in one part of a verb may, with different environment, remain unbroken even in another part in which it is stressed: ✱volēre ＞ volẹr, ✱vŏleo ＞ vuelh, ✱vŏlet ＞ vǫl. If the breaking occurs in the 1st pers. sg., the phonetic development is regularly undisturbed; if it occurs in the 2d and 3d pers. sg., it is generally carried into the other forms in which the vowel is stressed: cŏllĭgit ＞ cuęlh, hence cuęlh = collĭgo; ĕxit ＞ ięis, hence ięsc, ięscon, ięsca.
160. A consonant may be followed by e̯ or i̯, and so palatalized, in one part of the verb, and not in another: ✱cadeo ＞ chai, ✱cadēmu’ ＞ chazẹm; dēbeo ＞ dẹch dẹi (§ [73], βy), dēbet ＞ dẹu; faciat ＞ fassa, facĕre ＞ faire; fŭgio ＞ füi, fugĕre ＞ fugir; jaceam ＞ iassa, jacēre ＞ iazẹr[118]; placeāmu’ ＞ plassám, placēmu’ ＞ plazẹm; sapiam ＞ sapcha, sapit ＞ sap; tĕneo ＞ tenh, tĕnet ＞ ten; valeo ＞ valh, vales ＞ vals; vĕniat ＞ venha, venīre ＞ venir; vĭdeam ＞ vẹia, vidētis ＞ vezẹtz; ✱vŏleo ＞ vuęlh, ✱vŏlet ＞ vǫl. Verbs in -eo generally keep this distinction; but we find mǫva, somóna, tẹma = mŏveam, submŏneam, tĭmeam. Most verbs in -io, on the other hand, dropped the i̯ in Vulgar Latin: partio ✱parto ＞ part, partiunt ✱partunt ＞ parton, partiam ✱partam ＞ parta; sen, senton, senta; sięrf, sięrvon, sięrva; etc. A few verbs show forms both with and without the e̯ or i̯: audio ＞ auch (audiam ＞ auia), ✱audo ＞ au; crēdo ＞ crẹ, ✱crēdeo ＞ crẹi[119]; vĭdeo ＞ vẹi[119], ✱vĭdo ＞ vẹ.
161. Verbs in -ng- naturally developed a palatal consonant before e or i (§ [73], Ng´), but not before other vowels: cĭngĕre ＞ cẹnher, cĭngo ＞ cẹnc, cĭngit ＞ cẹnh, cĭngam ＞ cẹnga; so fẹnher, ọnher, plánher, pọnher, etc. The palatal was carried by analogy into the parts that were originally without it: hence the double forms cẹnc cẹnh, cẹngon cẹnhon, cẹnga cẹnha, etc. These double forms led tenẹr, venir to adopt tenc, venc, tenga, venga, beside the regular tenh, venh, tenha, venha. Such forms as these, supported by dẹrc ＜ de-ērĭgo, dic ＜ dīco, pręc ＜ prĕco, sęc ＜ ✱sequo, trac ＜ ✱trago, etc., afforded a starting-point for an ending -c, adopted by some other verbs in the 1st pers. sg. of the present indicative: pĕrdo ＞ pęrt pęrc, pr(eh)ĕndo ＞ pren prenc, remaneo ＞ remanh remanc, etc.
Peculiar Forms.
162. The following verbs have individual peculiarities that call for special mention:—
(1) Anar (＜ annāre), ‘to go’, takes most of its present from vadĕre: indicative, vau vauc (analogy of estau estauc), vas, va vai (analogy of fai), anám, anátz, van vaun (analogy of estan estaun); subjunctive, an or vaza (＜ vadam) vaia (analogy of vai and of traia), vaga (analogy of traga), etc.; imperative, vai (analogy of fai), anátz.
(2) Aucire (＜ occīidĕre: § [43]) has in the pres. indicative 3d sg. auci (＜ occīdit) and aucis (analogy of aucizém, aucizétz). Cf. auzir, caire, rire, traire, vezér. These forms were doubtless helped by the analogy of ditz (＜ dīcit), dütz, fatz, iatz, letz (＜ lĭcet), platz, tatz.