Esperanto Grammar - Parts of Speech

Parts of Speech

The suffixes -o, -a, -e, and -i indicate that a word is a noun, adjective, adverb, and infinitive verb, respectively. Many new words can be derived simply by changing these suffixes, just as -ly derives adverbs from adjectives in English: From vidi (to see), we get vida (visual), vide (visually), and vido (sight).

Each root word has an inherent part of speech: nominal, adjectival, verbal, or adverbial. These must be memorized explicitly and affect the use of the part-of-speech suffixes. With an adjectival or verbal root, the nominal suffix -o indicates an abstraction: parolo (an act of speech, one's word) from the verbal root paroli (to speak); belo (beauty) from the adjectival root bela (beautiful); whereas with a noun, the nominal suffix simply indicates the noun. Nominal or verbal roots may likewise be modified with the adjectival suffix -a: reĝa (royal), from the nominal root reĝo (a king); parola (spoken). The various verbal endings mean to be when added to an adjectival root: beli (to be beautiful); and with a nominal root they mean to act as the noun, to use the noun, etc., depending on the semantics of the root: reĝi (to reign). There are relatively few adverbial roots, so most words ending in -e are derived: bele (beautifully). Often with a nominal or verbal root, the English equivalent is a prepositional phrase: parole (by speech, orally); vide (by sight, visually); reĝe (like a king, royally).

The meanings of part-of-speech affixes depend on the inherent part of speech of the root they are applied to. For example, brosi (to brush) is based on a nominal root (and therefore listed in modern dictionaries under the entry broso), whereas kombi (to comb) is based on a verbal root (and therefore listed under kombi). Change the suffix to -o, and the similar meanings of brosi and kombi diverge: broso is a brush, the name of an instrument, whereas kombo is a combing, the name of an action. That is, changing verbal kombi (to comb) to a noun simply creates the name for the action; for the name of the tool, the suffix -ilo is used, which derives words for instruments from verbal roots: kombilo (a comb). On the other hand, changing the nominal root broso (a brush) to a verb gives the action associated with that noun, brosi (to brush). For the name of the action, the suffix -ado will change a derived verb back to a noun: brosado (a brushing). Similarly, an abstraction of a nominal root (changing it to an adjective and then back to a noun) requires the suffix -eco, as in infaneco (childhood), but an abstraction of an adjectival or verbal root merely requires the nominal -o: belo (beauty). Nevertheless, redundantly affixed forms such as beleco are acceptable and widely used.

A limited number of basic adverbs do not end with -e, but with an undefined part-of-speech ending -aŭ. Not all words ending in -aŭ are adverbs, and most of the adverbs that end in -aŭ have other functions, such as hodiaŭ "today" or ankoraŭ "yet, still" . About a dozen other adverbs are bare roots, such as nun "now", tro "too, too much", not counting the adverbs among the correlatives. (See special Esperanto adverbs.)

Other parts of speech occur as bare roots, without special suffixes. These are the prepositions (al "to"), conjunctions (kaj "and"), interjections (ho "oh"), numerals (du "two"), and pronouns (mi "I"—The final -i found on pronouns is not a suffix, but part of the root). There are also several grammatical "particles" which don't fit neatly into any category, and which must generally precede the words they modify, such as ne (not), ankaŭ (also), nur (only), eĉ (even).

The part-of-speech endings may be iterated. With the -aŭ suffix, this is nearly universal, and the -aŭ is rarely dropped: anstataŭ 'instead of', anstataŭe 'instead', anstantaŭa 'substitute', anstataŭo 'a substitute', anstataŭi 'to replace', etc. (Rarely anstate, anstata, anstato, anstati.) In the case of prepositions and particles, there is nothing to drop: nea 'negative', nei 'to deny'. However, occasionally other endings double up. For example, vivu! "viva!" (the volitive of vivi 'to live') has a nominal form vivuo (a cry of 'viva!') and a doubly verbal form vivui (to cry 'viva!').