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 The cognates derived from these roots in different daughter languages often do not agree in formation, but show certain characteristic properties: The comparative form ("bigger, more beautiful") could be formed by replacing an adjective's suffix with ; the resulting word is amphikinetic: 'big' (Latin "magnus") → 'bigger' (Latin "maior, maius"), weak cases . A second suffix, , originally expressed contrast, as in Ancient Greek "pó-tero-s" 'which (of two)' or "dexi-teró-s" 'right (as opposed to left)'. It later attained comparative function. For example, the meaning of Ancient Greek "sophṓteros" 'wiser, the wiser one' developed from 'the wise one (of the two)'.