Umbrian is an extinct Italic language formerly spoken by the Umbri in the ancient Italian region of Umbria.

Since that classification was first formulated, a number of other languages in ancient Italy were discovered to be more closely related to Umbrian.

Examples from long a-stems (for use of bold versus italic script, see above under "Alphabet"): Singular: Nom.

[10] This irregularity also appears in a select few first conjugation Latin verbs, such as the perfect form domui from domare.

These verbs, both meaning "to be," evolved into the Umbrian form fust, which possibly predicated the development of the similar future perfect endings.

Alternatively, it may have emerged due to the generalization of the zero-grade Proto-Indo-European perfect active participle root *-us- or the lengthened grade *-uōs- , itself possibly from *-uūs-.

Remnants of this technique appear in Umbrian verbs such as peperscust, in which the initial consonant of p- is reduplicated with an -e- vowel added between the two letters.

For instance, in the case of andirsafust, the term may have originated from the am-di-da-nt-s fust, although this etymology specifically is disputed.

[24] The etymological origins of this root are unclear, it may have emerged from a reconstructed Proto-Italic form *-nki-, itself possibly related to Proto-Indo-European *h₁neḱ- ("to bear, to bring.").

In Umbrian, the passive voice may have additionally partially fulfilled the role of the middle voice: The Umbrian verb amparihmu, a passive form, was utilized to express the middle meaning of "to raise, elevate oneself;" "to rise."

[31] The Umbrian present imperative is exclusively attested in two first conjugation forms: aserio ("observe") and stiplo ("bargain"), both substituting the final -ā for -ō.

This jussive function of the subjunctive appears throughout the Iguvine tablets, which decree "fust eikvasese Atiierier, ere ri esune kuraia, prehabia pife uraku ri esuna," meaning "[the Flamen] shall have the care of the sacred affair; he shall furnish whatever is necessary.

"[34] Carl Darling Buck, an American philologist, argued that, in the attested Umbrian corpus, the jussive subjunctive and the imperative were used largely interchangeably.

Jones suggests that, while the imperative considered specific instructions, the jussive subjunctive was largely limited to descriptions of duties or punishments for officials.

[36] Thus, the aforementioned sentences utilized the subjunctive as they were outlining ritual practices for Flamini, while statements such as "di grabouie pihatu" (Jupiter Grabovius, purify!)

[37] In negative commands, which call for something to not occur, Umbrian primarily utilizes the imperative, although the subjunctive form neiřhabas appears in one inscription to mean "let them not use.

"[38] Furthermore, this term appears to violate the previously established distinction between the subjunctive and the imperative, as it used as an explicit instruction.

The full sentence, reading "huntak piři prupehast eřek ures punes neiřhabas," may translate to "When he has purified the jar, thereafter they shall not use any of that mead.

However, Jones instead opts to resolve this anomaly with the translation "during the preliminary purification of the huntak the aforesaid mead is not to be used."

Jones argues that this interpretation is not just a more accurate translation but also ensures consistency with the standard rules of the Umbrian subjunctive as—in his version—the prohibitive command is distinct from the actual section of the description of the ritual that first mentions the mead, and thus, there is some level of discontinuity between the two pieces of the text.

[43] Another Umbrian conjunction, sue or—alternatively—sve, meaning "if" (compare Latin "si"), was involved in indirect questions: the Umbrian sentence "Sve mestru karu fratru Atiief iu, pure ulu benurent, prusikurent kuratu rehte neip eru, enuk fratru ehvelklu feia fratreks ute kvestur, panta muta arferture si."

[45] One example of a conditional clause without an introductory conjunction appears in the Iguvine tablets, which stipulates "Heriiei façiu arfertur... kurçlasiu façia tiçit," meaning "if the flamen wishes to make the sacrifice, it is proper.

"[46] Jones suggests that the uses of the subjunctive may have extended to invocation, citing another passage from the Iguvine tablets which reads "di grabouie tio subocau."

According to Jones, this statement utilizes a subjunctive form of "subocau" to mean "Jupiter Grabovius, I invoke thee.

"[37] Verbs in Umbrian are inflected for the following categories:[47] Present, future and future perfect forms in the active voice use the following set of personal endings (primary):[48] Imperfect, perfect indicative and all tenses of the subjunctive in the active voice use a different set of endings (secondary):[48] Passive endings are attested only for the 3rd person: singular primary -ter, singular secondary -(n)tur, plural -endi.

[60] But compared to its highly conservative sister language Oscan, Umbrian exhibits a number of innovations, some of them shared by its neighbor to the west, Latin.

For example, the genitive plural ending of -ā stems: Umbrian -arum, Latin -arum vs Oscan -asúm (compare Sanskrit -āsām).