Editing Esperanto grammar (section)

==Prepositions==
Although Esperanto [[word order]] is fairly free, [[preposition]]s must come at the beginning of a [[noun phrase]]. Whereas in languages such as German, prepositions may require that a noun be in various [[case (linguistics)|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:
:''ili iros '''je''' la tria de majo'' (they'll go on the third of May: the "on" isn't literally true).

Alternatively, the accusative may be used without a preposition:
:''ili iros la tria'''n''' de majo.''

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 case|allative construction]]). It is especially common when there would otherwise be a double preposition:
:''la kato ĉasis la muson '''en''' la domo'' (the cat chased the mouse '''in''' [inside of] the house)
:''la kato ĉasis la muson '''en''' la domo'''n''''' (the cat chased the mouse '''into''' the house).

The accusative/allative may stand in for other prepositions also, especially when they have vague meanings that do not add much to the clause. Adverbs, with or without the case suffix, are frequently used instead of prepositional phrases:
:''li iris '''al''' sia hejmo'' (he went to his home)
:''li iris hejme'''n''''' (he went home)

Both ''por'' and ''pro'' can correspond to English 'for'. However, ''por'' indicates ''for a goal'' (the more usual sense of English 'for') while ''pro'' indicates ''for a cause'' and more often may be translated 'because of': 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 because of something that happened to them or something they said or did.

The preposition most distinct from English usage is perhaps ''de'', which corresponds to English ''of, from, off,'' and ''(done) by'':
:''libro '''de''' Johano'' (John''''s''' book)
:''li venis '''de''' la butiko'' (he came '''from''' the shop)
:''mordita '''de''' hundo'' (bitten '''by''' a dog)

However, English ''of'' corresponds to several Esperanto prepositions also: ''de, el'' (out of, made of), and ''da'' (quantity of, unity of form and contents):
:''tablo '''el''' ligno'' (a table '''of''' wood)
:''glaso '''da''' vino'' (a glass '''of''' wine)
:''listo '''da''' kondiĉoj '''de''' la kandidatoj'' (a list '''of''' conditions '''from''' the candidates)
The last of these, ''[[wikt:da#Esperanto|da]]'', is semantically Slavic and is difficult for Western Europeans, to the extent that even many Esperanto dictionaries and grammars define it incorrectly.<ref>Sergio Pokrovskij, 2007. "[https://lingvakritiko.com/2007/02/05/la-artikolo/#Da La artikolo]", in ''Lingva Kritiko: Studoj kaj notoj pri la Internacia Lingvo''.<br/>See the entry for [[wikt:da#Esperanto|''da'' at Wiktionary]].</ref>

Because a bare [[root (linguistics)|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. Thus the verbal root ''far-'' (do, make) has been unofficially used without a part-of-speech suffix as a preposition "by", marking the agent of a passive participle or an action noun in place of the standard ''de''.