THE NOUN (La Substantivo).

103. A noun (in the singular number) in all its cases, except the accusative, ends in -O. The accusative is formed by the addition of N. In the plural it ends in -OJ, and the accusative plural is formed by adding N to these letters. Thus the root arb- is made into a noun with its numbers and cases as follows:—

Arb-o = a tree (nominative, singular).
Arb-on = a tree (accusative, singular).
Arb-oj = trees (nominative, plural).
Arb-ojn = trees (accusative, plural).

Examples.—Domo = A house. La domo = The house. La domoj = The houses. Rigardu la domojn = Look at the houses. Knabo = A boy. La knabo = The boy. Mi vidis la knabon = I saw the boy. Knabino = A girl. La knabino = The girl.

Declension of Nouns, Adjectives, and Pronouns.

104. There are but two cases in Esperanto (Rule 2, par. [94]), viz., the nominative and the accusative (or objective); the latter is obtained from the nominative by adding N to the singular or plural. Other cases are expressed by the aid of prepositions, as:—

Nominative	Mia bona patro	= My good father.
Accusative	Mian bonan patron	= My good father.
Genitive or Possessive	De mia bona patro	= Of my good father, or, My good father’s.
Dative	Al mia bona patro	= To my good father.
Ablative	De mia bona patro	= From (by, see par. [259 (9)]) my good father.
	Kun mia bona patro	= With my good father.
	Per bona glavo	= With (by means of) a good sword.

Note that per = by is the instrumental ablative, meaning "by means, or aid, or use, of," and that kun = with means "in company with," but not in an instrumental sense, as it is sometimes in English, e.g., I held him with both hands = Mi lin tenis per ambaŭ manoj, not kun ambaŭ manoj (see par. [259 (22)]).

Plural.

(a). In the plural the declension is the same, with the addition of the plural termination J, as:—

Genitive	De miaj bonaj filoj	= Of my good sons.
Accusative	Miajn bonajn filojn	= My good sons.

Examples.—La frato skribas, kaj la fratino legas = The brother is writing and the sister reading. La patro donis la libron al sia filo = The father gave the book to his son. Tiu ĉi kaŭĉuka ringo (or, ringo el kaŭĉuko) estas por la infaneto = This india-rubber ring is for the baby. Mi vidis Jozefon kun lia kuzo = I saw Joseph with his cousin. Venu, ni atendas Vin (Cin), Savinto de la mondo = Come, we await You (Thee), O Saviour of the world. Mi lin salutis per la mano = I saluted him by the hand. La domo estas kovrita per ardezoj = The house is covered with slates. Mi vidis vian patron kun liaj du filoj = I saw your father with his two sons. Kie estas la domo de via patro? = Where is your father’s house?

105. Ellipsis.—The case (nominative or accusative) of words in Esperanto often depends upon the verb omitted when ellipsis occurs in a phrase, and

unless we write the sentence in full, or think what the ellipsis is, we may not at first know what case to use to express our meaning. A glance at the following examples will show how easy it is to determine the case. The words in brackets show the ellipsis:—

Mi konas lin pli bone, ol vi (konas lin) = I know him better than you (do, or know him).
Mi konas lin pli bone, ol vin (ol mi konas vin) = I know him better than you (than I know you).
Petro amas Paŭlon tiom, kiom (li amas) Johanon = Peter loves Paul as much as (he loves) John.
Petro amas Paŭlon tiom, kiom Johano (amas lin) = Peter loves Paul as much as John (loves him).

N.B.—In the above sentences we cannot, in English, tell the meaning until the ellipsis is supplied, whereas, in Esperanto, the meaning is at once clear from the case of the noun or pronoun (par. [112]).

Li iris tien, kiel ankaŭ vi (iris) = He went there as well as you (went).
Mi vidis lin tie, kiel ankaŭ (mi vidis) vin = I saw him there as well as (I saw) you.
Mi neniam vidis tian hundon, kia (estas) via = I never saw such a dog as yours.

105 (a). Elision.—The final O of a noun may be omitted (par. [57], and Rule 16, par. [94]).

106. Possession is (a) expressed by help of the preposition de.

Examples.—La domo de la patro = The father’s house, or, the house of the father. La libro de mia patrino = My mother’s book, or, the book of my mother. La tranĉilo de Georgo = George’s knife. Tio estas la domo de miaj fratoj = That is my brothers’ house (the house of my brothers). (See par. [73].)

(b). Possession is also denoted by the correlative words ending in ES, viz.:—ies = someone’s, somebody’s, ĉies = everyone’s, kies = whose, nenies = nobody’s, ties = that one’s, of those (see par. [154]).

Examples.—Ĉies ideo estis diversa = Everyone’s idea was different. Kies domo estas tiu? = Whose house is that? Ĝi estas nenies domo = It is nobody’s house. Ĉu ĉi tio estas ies tranĉilo? = Is this anyone’s (someone’s) knife? (see par. [154]).

(c). An adjective is sometimes conveniently used when in English we employ an apostrophe.

Examples.—Unutaga laboro (for, la laboro de unu tago) = One day’s work. La unuataga laboro (for, la laboro de la unua tago) = The first day’s work. Lia unuataga laboro estis en la ĝardeno, kaj poste li faris unutagan laboron en la domo = His first day’s work was in the garden, and then (afterwards) he did one day’s work in the house. Mi atendis la kapitanan respondon = I awaited the captain’s reply.

(d). In speaking of places, the English preposition "of" is not translated.

Examples.—La urbo Londono = The City of London. La Kolonio Natalo = The Colony of Natal (see par. [253] (a)).

For numeral nouns, see par. [118]; for participial, pars. [208], [209]; for predicative, par. [109]; for compound nouns, par. [49]; for form of accusative with proper names, par. [69] (d); for the infinitive used as a noun, par. [180].