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
Esperanto words with the suffix -um Esperanto words with the suffix -um Esperanto derivation is for the most part regular and predictable: One can normally understand new words that are built upon known roots, and can create new words on the fly while speaking. However, there is a suffix "-um-" that has no inherent meaning, but derives words that cannot be readily derived with dedicated affixes. Such derivations must be memorized individually, though because the root already exists, they may be more easily learned than a completely new word. Because of its irregularity and unpredictability, over-use of the suffix "-um-" is discouraged. Over time substitutes have