Indo-European copula copula (with corresponding voiceless and voiced fricatives) existed side by side in Germanic, and the involvement of a separate root "" is unnecessary. The root "*(s)teh-" meant "to stand". From this root comes the present stem of the so-called "substantive verb" in Irish and Scottish Gaelic, "tá" and "tha" respectively. On the absence of the initial s- in Celtic, see Indo-European s-mobile. In Latin, "stō, stare" retained the meaning "to stand", until local forms of Vulgar Latin began to use it as a copula in certain circumstances. Today, this survives in that several Romance languages (Galician-Portuguese, Spanish, Catalan) use it
Proto-Indo-European nominals two declensions, the o-stems, are thematic, and all others are athematic. Morpheme boundaries (boundaries between root, suffix, and ending) are given only in the nominative singular. Proto-Indo-European nominals Proto-Indo-European nominals include nouns, adjectives and pronouns. Their grammatical forms and meanings have been reconstructed by modern linguists, based on similarities found across all Indo-European languages. This article discusses nouns and adjectives, and Proto-Indo-European pronouns are treated elsewhere. PIE had eight or nine cases, three numbers (singular, dual and plural) and probably originally two genders (animate and neuter), with the animate later splitting into the masculine and the feminine. Nominals fell into