Some of this article's listed sources may not be reliable.August 2017) ()(
Each part of speech has a unique suffix: nouns end with ‑o; adjectives with ‑a; present‑tense indicative verbs with ‑as, and so on.
It is possible to communicate effectively with a vocabulary of 400 to 500 "meaning words", though more exist in the language. The original vocabulary of Esperanto had around 900 meaning words, but was quickly expanded.
Reference grammars include the Plena Analiza Gramatiko (eo) (English: Complete Analytical Grammar) by Kálmán Kalocsay and Gaston Waringhien, and the Plena Manlibro de Esperanta Gramatiko (English: Complete Handbook of Esperanto Grammar) by Bertilo Wennergren.
Esperanto has an agglutinative morphology, no grammatical gender, and simple verbal and nominal inflections. Verbal suffixes indicate four moods, of which the indicative has three tenses, and are derived for several aspects, but do not agree with the grammatical person or number of their subjects. Nouns and adjectives have two cases, nominative/oblique and accusative/allative, and two numbers, singular and plural; the adjectival form of personal pronouns behaves like a genitive case. Adjectives generally agree with nouns in case and number. In addition to indicating direct objects, the accusative/allative case is used with nouns, adjectives and adverbs for showing the destination of a motion, or for replacing certain prepositions; the nominative/oblique is used in all other situations. The case system allows for a flexible word order that reflects information flow and other pragmatic concerns, as in Russian, Greek, and Latin.
Esperanto uses the Latin alphabet with six additional letters – ĉ, ĝ, ĥ, ĵ, ŝ, and ŭ – and does not use the letters q, w, x, or y.
Esperanto has a single definite article, la, which is invariable. It is similar to English "the".
La is used:
There is no grammatically required indefinite article: homo means either "human being" or "a human being", depending on the context, and similarly the plural homoj means "human beings" or "some human beings". The words iu and unu (or their plurals iuj and unuj) may be used somewhat like indefinite articles, but they're closer in meaning to "some" and "a certain" than to English "a". This use of unu corresponds to English "a" when the "a" indicates a specific individual.
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. Derivations from the word vidi (to see) are vida (visual), vide (visually), and vido (vision).
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" [noun or adverb] or ankoraŭ "yet, still" [conjunction or adverb]. 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" that fit neatly into no category, and which must generally precede the words they modify, such as ne (not), ankaŭ (also), nur (only), eĉ (even).
A suffix -j following the noun or adjective suffixes -o or -a makes a word plural. Without this suffix, a countable noun is understood to be singular. Direct objects take an accusative case suffix -n, which goes after any plural suffix. (The resulting sequence -ojn rhymes with English coin, and -ajn rhymes with fine.)
Adjectives agree with nouns. That is, they are plural if the nouns that they modify are plural, and accusative if the nouns that they modify are accusative. Compare bona tago; bonaj tagoj; bonan tagon; bonajn tagojn (good day/days). This requirement allows for free word orders of adjective-noun and noun-adjective, even when two noun phrases are adjacent in subject–object–verb or verb–subject–object clauses:
Agreement clarifies the syntax in other ways also. Adjectives take the plural suffix when they modify more than one noun, even if those nouns are all singular:
A predicative adjective does not take the accusative case suffix even when the noun that it modifies does:
There are three types of pronouns in Esperanto: personal (vi "you"), demonstrative (tio "that", iu "someone"), and relative/interrogative (kio "what"). According to the fifth rule of the Fundamento de Esperanto:
5. The personal pronouns are: mi, "I"; vi, "thou", "you"; li, "he"; ŝi, "she"; ĝi, "it"; si, "self"; ni, "we"; ili, "they"; oni, "one", "people", (French "on").— L. L. Zamenhof, Fundamento de Esperanto (1905)
|first person||mi (I)||ni (we)|
|second person||vi (you)1|
|masculine||li (he)||ili (they)|
|indefinite||oni (one, they, you)|
^¹ Zamenhof introduced the singular second-person pronoun ci to be used in translations from languages where the T–V distinction is important, and added it in the Dua Libro in 1888 clarifying that "this word is only found in the dictionary; in the language itself it is hardly ever used". It has never been widely used, even by Zamenhof himself, who didn't include it as a pronoun in the 5th rule of the Fundamento and in his 28th Lingva Respondo, published in 1908, recommended to use only vi. The normal usage is to use vi regardless of number or formality. However, especially in some circles, people have begun to use ci in practical speech.
Personal pronouns take the accusative suffix -n as nouns do: min (me), lin (him), ŝin (her). Possessive adjectives are formed with the adjectival suffix -a: mia (my), ĝia (its), nia (our). These agree with their noun like any other adjective: ni salutis liajn amikojn (we greeted his friends). Esperanto does not have separate forms for the possessive pronouns; this sense is generally (though not always) indicated with the definite article: la mia (mine).
The reflexive pronoun is used, in non-subject phrases only, to refer back to the subject, usually only in the third and indefinite persons:
The indefinite pronoun is used when making general statements, and is often used where English would have the subject it with a passive verb,
With "impersonal" verbs where there is actually no item or being that is doing an action, no pronoun is used:
The rain is falling by itself, therefore the subject pronoun is omitted.
Ĝi ("it"; third person neutral) is mostly used with items that have physical bodies. Zamenhof proposed that this pronoun can also be used as an epicene (gender-neutral) third-person singular pronoun, meaning for use when the gender of an individual is unknown or for when the speaker simply doesn't wish to clarify the gender. However, this proposal is not generally accepted.
In popular usage it's usually only used when referring to children:
When speaking of adults or people in general, in popular usage it is much more common for the demonstrative adjective and pronoun tiu ("that thing or person that is already known to the listener") to be used in such situations. This mirrors languages such as Japanese, but it's not a method that can always be used. For example, in the sentence
the word tiu would be understood as referring to someone other than the person speaking (like English pronouns this or that but also referring to people), and so cannot be used in place of ĝi, li or ŝi.
The demonstrative and relative pronouns form part of the correlative system, and are described in that article. The pronouns are the forms ending in -o (simple pronouns) and -u (adjectival pronouns). Their accusative case is formed in -n, but the genitive case ends in -es, which is the same for singular and plural and does not take accusative marking. Compare the nominative phases lia domo (his house) and ties domo (that one's house, those ones' house) with the plural liaj domoj (his houses) and ties domoj (that one's houses, those ones' houses), and with the accusative genitive lian domon and ties domon.
Ri and ria are unofficial pronouns, that some Esperanto speakers use to refer to a single person regardless of their gender identity. Some Esperanto speakers use it only to refer to a single person whose gender identity is unknown or non-binary or to refer to unspecified person, while other Esperanto speakers use it also to refer to a person whose gender identity is purely female or purely male. E. g. Ĉiu amas ordinare personon, kiu estas simila al ri ("Everybody usually loves a person who is similar to them"); Alekso kaj ria amiko estas ambaŭ neduumaj ("Alex and their friend are both non-binary"). The use of the Esperanto pronoun ri is (almost) the same as the use of the English singular they and the Swedish pronoun hen.
Although Esperanto word order is fairly free, prepositions must come at the beginning of a noun phrase. Whereas in languages such as German, prepositions may require that a noun be in various cases (accusative, dative, and so on), in Esperanto all prepositions govern the nominative: por Johano (for John). The only exception is when there are two or more prepositions and one is replaced by the accusative.
Prepositions should be used with a definite meaning. When no one preposition is clearly correct, the indefinite preposition je should be used:
Alternatively, the accusative may be used without a preposition:
Note that although la trian (the third) is in the accusative, de majo (of May) is still a prepositional phrase, and so the noun majo remains in the nominative case.
A frequent use of the accusative is in place of al (to) to indicate the direction or goal of motion (allative construction). It is especially common when there would otherwise be a double preposition:
The accusative/allative may stand in for other prepositions also, especially when they have vague meanings that add not much to the clause. Adverbs, with or without the case suffix, are frequently used instead of prepositional phrases:
Both por and pro often translate English 'for'. However, they distinguish for a goal (looking forward in time, or causing: por) and for a cause (looking back in time, or being caused by: pro): To vote por your friend means to cast a ballot with their name on it, whereas to vote pro your friend would mean to vote in their place or as they asked you to.
The preposition most distinct from English usage is perhaps de, which corresponds to English of, from, off, and (done) by:
However, English of corresponds to several Esperanto prepositions also: de, el (out of, made of), and da (quantity of, unity of form and contents):
Occasionally a new preposition is coined. Because a bare root may indicate a preposition or interjection, removing the grammatical suffix from another part of speech can be used to derive a preposition or interjection. For example, from fari (to do, to make) we get the preposition far (done by).
All verbal inflection is regular. There are three tenses, all of which are in the indicative mood. The other moods are the infinitive, conditional, and jussive. No aspectual distinctions are required by the grammar, but derivational expressions of Aktionsart are common.
Verbs do not change form according to their subject. I am, we are, and he is are simply mi estas, ni estas, and li estas, respectively. Impersonal subjects are not used: pluvas (it is raining); estas muso en la domo (there's a mouse in the house).
Most verbs are inherently transitive or intransitive. As with the inherent part of speech of a root, this is not apparent from the shape of the verb and must simply be memorized. Transitivity is changed with the suffixes -ig- (the transitivizer/causative) and -iĝ- (the intransitivizer/middle voice):
The tenses have characteristic vowels. A indicates the present tense, i the past, and o the future.
|Indicative||Active participle||Passive participle||Infinitive||Jussive (volitive)||Conditional|
The verbal forms may be illustrated with the root esper- (hope):
A verb can be made emphatic with the particle ja (indeed): mi ja esperas (I do hope), mi ja esperis (I did hope).
As in English, Esperanto present tense may be used for generic statements such as "birds fly" (la birdoj flugas).
The Esperanto future is a true tense, used whenever future time is meant. For example, in English "(I'll give it to you) when I see you" the verb "see" is in the present tense despite the time being in the future; in Esperanto, future tense is required: (Mi donos ĝin al vi) kiam mi vidos vin.
Esperanto tense is relative. This differs from English absolute tense, where the tense is past, present, or future of the moment of speaking: In Esperanto, the tense of a subordinate verb is instead anterior or posterior to the time of the main verb. For example, "John said that he would go" is in Esperanto Johano diris, ke li iros (lit., "John said that he will go"); this does not mean that he will go at some point in the future from now (as "John said that he will go" means in English), but that at the time he said this, his going was still in the future.
The conditional mood is used for such expressions as se mi povus, mi irus (if I could, I would go) and se mi estus vi, mi irus (if I were you, I'd go).
The verb esti (to be) is both the copula ("X is Y") and the existential ("there is") verb. As a copula linking two noun phrases, it causes neither to take the accusative case. Therefore, unlike the situation with other verbs, word order with esti can be semantically important: compare hundoj estas personoj (dogs are people) and personoj estas hundoj (people are dogs).
citation needed] This is a stylistic rather than grammatical change in the language, as the more economical verbal forms were always found in poetry.[
Participles are verbal derivatives. In Esperanto, there are six forms:
The participles represent aspect by retaining the vowel of the related verbal tense: i, a, o. In addition to carrying aspect, participles are the principal means of representing voice, with either nt or t following the vowel (see next section).
The basic principle of the participles may be illustrated with the verb fali (to fall). Picture a cartoon character running off a cliff. Before the character falls, they are falonta (about to fall). As they drop, they are falanta (falling). After they hit the ground, they are falinta (fallen).
Active and passive pairs can be illustrated with the transitive verb haki (to chop). Picture a woodsman approaching a tree with an axe, intending to chop it down. He is hakonta (about to chop) and the tree is hakota (about to be chopped). While swinging the axe, he is hakanta (chopping) and the tree hakata (being chopped). After the tree has fallen, he is hakinta (having chopped) and the tree hakita (chopped).
Adjectival participles agree with nouns in number and case, just as other adjectives do:
Compound tenses are formed with the adjectival participles plus esti (to be) as the auxiliary verb. The participle reflects aspect and voice, while the verb carries tense:
These are not used as often as their English equivalents. For "I am going to the store", you would normally use the simple present mi iras in Esperanto.
The tense and mood of esti can be changed in these compound tenses:
Although such periphrastic constructions are familiar to speakers of most European languages, the option of contracting [esti + adjective] into a verb is often seen for adjectival participles:
The active synthetic forms are:
|Present tense||mi kaptas
(I am catching)
(I have caught)
|mi kaptontas |
(I am about to catch)
|Past tense||mi kaptis
(I was catching)
(I had caught)
|mi kaptontis |
(I was about to catch)
|Future tense||mi kaptos
(I will catch)
(I will be catching)
(I will have caught)
|mi kaptontos |
(I will be about to catch)
|Conditional mood||mi kaptus
(I would catch)
(I would be catching)
(I would have caught)
|mi kaptontus |
(I would be about to catch)
Infinitive and jussive forms are also found. There is a parallel passive paradigm. A few of these forms, notably -intus and -atas, entered common usage, but most of them are very rare because they are difficult to understand.
Participles may be turned into adverbs or nouns by replacing the adjectival suffix -a with -e or -o. This means that, in Esperanto, some nouns may be inflected for tense.
A nominal participle indicates one who participates in the action specified by the verbal root. For example, esperinto is a "hoper" (past tense), or one who had been hoping.
Adverbial participles are used with subjectless clauses:
Occasionally, the participle paradigm will be extended to include conditional participles, with the vowel u (-unt-, -ut-). If, for example, in our tree-chopping example, the woodsman found that the tree had been spiked and so couldn't be cut down after all, he would be hakunta and the tree hakuta (he, the one "who would chop", and the tree, the one that "would be chopped").
This can also be illustrated with the verb prezidi (to preside). Just after the recount of the 2000 United States presidential election:
The tense-neutral word prezidento is officially a separate root, not a derivative of the verb prezidi.
A statement is made negative by using ne or one of the negative (neni-) correlatives. Ordinarily, only one negative word is allowed per clause:
Two negatives within a clause cancel each other out, with the result being a positive sentence.
The word ne comes before the word it negates:
The latter will frequently be reordered as ne tion mi skribis depending on the flow of information.
"Wh" questions are asked with one of the interrogative/relative (ki-) correlatives. They are commonly placed at the beginning of the sentence, but different word orders are allowed for stress:
Yes/no questions are marked with the conjunction ĉu (whether):
Such questions can be answered jes (yes) or ne (no) in the European fashion of aligning with the polarity of the answer, or ĝuste (correct) or malĝuste (incorrect) in the Japanese fashion of aligning with the polarity of the question:
Note that Esperanto questions may have the same word order as statements.
Basic Esperanto conjunctions are kaj (both/and), kun (with),aŭ (either/or), nek (neither/nor), se (if), ĉu (whether/or), sed (but), anstataŭ (instead of), krom (besides, except for), kiel (like, as), ke (that). Like prepositions, they precede the phrase or clause they modify:
However, unlike prepositions, they allow the accusative case, as in the following example from Don Harlow:
Interjections may be derived from bare affixes or roots: ek! (get going!), from the perfective prefix; um (um, er), from the indefinite/undefined suffix; fek! (shit!), from feki (to defecate).
Esperanto derivational morphology uses a large number of lexical and grammatical affixes (prefixes and suffixes). These, along with compounding, decrease the memory load of the language, as they allow for the expansion of a relatively small number of basic roots into a large vocabulary. For example, the Esperanto root vid- (see) regularly corresponds to several dozen English words: see (saw, seen), sight, blind, vision, visual, visible, nonvisual, invisible, unsightly, glance, view, vista, panorama, observant etc., though there are also separate Esperanto roots for a couple of these concepts.
The cardinal numerals are:
These are grammatically numerals, not nouns, and as such do not take the accusative case suffix. However, unu (and only unu) is sometimes used adjectivally or demonstratively, meaning "a certain", and in such cases it may take the plural affix -j, just as the demonstrative pronoun tiu does:
In such use unu is irregular in that it doesn't take the accusative affix -n in the singular, but does in the plural:
Additionally, when counting off, the final u of unu may be dropped, as if it were a part-of-speech suffix:
At numbers beyond the thousands, the international roots miliono (million) and miliardo (milliard) are used. Beyond this there are two systems: A billion in most English-speaking countries is different from a billion in most other countries (109 vs. 1012 respectively; that is, a thousand million vs. a million million). The international root biliono is likewise ambiguous in Esperanto, and is deprecated for this reason. An unambiguous system based on adding the Esperanto suffix -iliono to numerals is generally used instead, sometimes supplemented by a second suffix -iliardo:
Note that these forms are grammatically nouns, not numerals, and therefore cannot modify a noun directly: mil homojn (a thousand people [accusative]) but milionon da homoj (a million people [accusative]).
Numerals are written together as one word when their values are multiplied, and separately when their values are added (dudek 20, dek du 12, dudek du 22). Ordinals are formed with the adjectival suffix -a, quantities with the nominal suffix -o, multiples with -obl-, fractions with ‑on‑, collectives with ‑op‑, and repetitions with the root ‑foj‑.
The particle po is used to mark distributive numbers, that is, the idea of distributing a certain number of items to each member of a group. Consequently, the logogram @ is not used (except in email addresses, of course):
Note that particle po forms a phrase with the numeral tri and is not a preposition for the noun phrase tri pomojn, so it does not prevent a grammatical object from taking the accusative case.
Comparisons are made with the adverbial correlatives tiel ... kiel (as ... as), the adverbial roots pli (more) and plej (most), the antonym prefix mal-, and the preposition ol (than):
Implied comparisons are made with tre (very) and tro (too [much]).
Phrases like "The more people, the smaller the portions" and "All the better!" are translated using ju and des in place of "the":
Esperanto has a fairly flexible word order. However, word order does play a role in Esperanto grammar, even if a much lesser role than it does in English. For example, the negative particle ne generally comes before the element being negated; negating the verb has the effect of negating the entire clause (or rather, there is ambiguity between negating the verb alone and negating the clause):
However, when the entire clause is negated, the ne may be left till last:
The last order reflects a typical topic–comment (or theme–rheme) order: Known information, the topic under discussion, is introduced first, and what one has to say about it follows. (I went not: As for my going, there was none.) For example, yet another order, ne iris mi, would suggest that the possibility of not having gone was under discussion, and mi is given as an example of one who did not go.
Within a noun phrase, either the order adjective–noun or noun–adjective may occur, though the former is somewhat more common. Less flexibility occurs with numerals and demonstratives, with numeral–noun and demonstrative–noun being the norm, as in English.
Adjective–noun order is much freer. With simple adjectives, adjective–noun order predominates, especially if the noun is long or complex. However, a long or complex adjective typically comes after the noun, in some cases parallel to structures in English, as in the second example below:
Adjectives also normally occur after correlative nouns. Again, this is one of the situations where adjectives come after nouns in English:
Changing the word order here can change the meaning, at least with the correlative nenio 'nothing':
With multiple words in a phrase, the order is typically demonstrative/pronoun–numeral–(adjective/noun):
However, the article la precedes a noun phrase:
In prepositional phrases, the preposition is required to come at the front of the noun phrase (that is, even before the article la), though it is commonly replaced by turning the noun into an adverb:
Constituent order within a clause is generally free, apart from copular clauses.
The default order is subject–verb–object, though any order may occur, with subject and object distinguished by case, and other constituents distinguished by prepositions:
The expectation of a topic–comment (theme–rheme) order apply here, so the context will influence word order: in la katon ĉasis la hundo, the cat is the topic of the conversation, and the dog is the news; in la hundo la katon ĉasis, the dog is the topic of the conversation, and it is the action of chasing that is the news; and in ĉasis la hundo la katon, the action of chasing is already the topic of discussion.
Context is required to tell whether
means the dog chased a cat which was in the garden, or there, in the garden, the dog chased the cat. These may be disambiguated with
Of course, if it chases the cat into the garden, the case of 'garden' would change:
Within copulative clauses, however, there are restrictions. Copulas are words such as esti 'be', iĝi 'become', resti 'remain', and ŝajni 'seem', for which neither noun phrase takes the accusative case. In such cases only two orders are generally found: noun-copula-predicate and, much less commonly, predicate-copula-noun.
Generally, if a characteristic of the noun is being described, the choice between the two orders is not important:
However, la vento sovaĝa estas is unclear, at least in writing, as it could be interpreted as 'the wild wind is', leaving the reader to ask, 'is what?'.
In the sentence above, la hundo ĉasis la katon, kiu estis en la ĝardeno 'the dog chased the cat, which was in the garden', the relative pronoun kiu 'which' is restricted to a position after the noun 'cat'. In general, relative clauses and attributive prepositional phrases follow the noun they modify.
Attributive prepositional phrases, which are dependent on nouns, include genitives (la libro de Johano 'John's book') as well as la kato en la ĝardeno 'the cat in the garden' in the example above. Their order cannot be reversed: neither *la de Johano libro nor *la en la ĝardeno kato is possible. This behavior is more restrictive than prepositional phrases which are dependent on verbs, and which can be moved around: both ĉasis en la ĝardeno and en la ĝardeno ĉasis are acceptable for 'chased in the garden'.
Relative clauses are similar, in that they are attributive and are subject to the same word-order constraint, except that rather than being linked by a preposition, the two elements are linked by a relative pronoun such as kiu 'which':
Note that the noun and its adjacent relative pronoun do not agree in case. Rather, their cases depend on their relationships with their respective verbs. However, they do agree in number:
Other word orders are possible, as long as the relative pronoun remains adjacent to the noun it depends on:
the inference is that the cat fled after the dog started to chase it, not that the dog chased a cat which was already fleeing. For the latter reading, the clause order would be reversed:
This distinction is lost in subordinate clauses such as the relative clauses in the previous section:
In written English, a comma disambiguates the two readings, but both typically have a comma in Esperanto.
Non-relative subordinate clauses are similarly restricted. They follow the conjunction ke 'that', as in,
Esperanto's vocabulary, syntax, and semantics derive predominantly from Indo-European national languages. Roots are typically Romance or Germanic in origin. The semantics shows a significant Slavic influence.
It is often claimed that there are elements of the grammar which are not found in these language families. Frequently mentioned is Esperanto's agglutinative morphology based on invariant morphemes, and the subsequent lack of ablaut (internal inflection of its roots), which Zamenhof himself thought would prove alien to non-Indo-European language speakers. Ablaut is an element of all the source languages; an English example is song sing sang sung. However, the majority of words in all Indo-European languages inflect without ablaut, as cat, cats and walk, walked do in English. (This is the so-called strong–weak dichotomy.) Historically, many Indo-European languages have expanded the range of their 'weak' inflections, and Esperanto has merely taken this development closer to its logical conclusion, with the only remaining ablaut being frozen in a few sets of semantically related roots such as pli, plej, plu (more, most, further), tre, tro (very, too much), and in the verbal morphemes ‑as, ‑anta, ‑ata; ‑is, ‑inta, ‑ita; ‑os, ‑onta, ‑ota; and ‑us.
Other features often cited as being nonstandard for an Indo-European language, such as the dedicated suffixes for different parts of speech, or the -o suffix for singular nouns, actually do occur in Indo‑European languages such as Russian. More pertinent is the accusative plural in -jn. Esperanto is superficially similar to the non‑Indo‑European Hungarian and Turkish languages—that is, it is similar in its mechanics, but not in use. None of these proposed "non-European" elements of the original Esperanto proposal were actually taken from non-European or non-Indo-European languages, and any similarities with those languages are accidental.
East Asian languages may have had some influence on the development of Esperanto grammar after its creation. The principally cited candidate is the replacement of predicate adjectives with verbs, such as la ĉielo bluas (the sky is blue) for la ĉielo estas blua and mia filino belu! (may my daughter be beautiful!) for the mia filino estu bela! mentioned above.
The morphologically complex words (see Esperanto word formation) are:
|"being made holy"|