Irish syntax

Irish syntax is rather different from that of most Indo-European languages, notably because of its VSO word order.

Normal word order

The normal word order in an Irish sentence is:
#Preverbal particle
#Verb
#Subject
#Direct object or predicate adjective
#Indirect object
#Location descriptor
#Manner descriptor
#Time descriptor

Only the verb and subject are obligatory; all other parts are optional (unless the primary or finite verb is transitive, in which case a direct object is required). In synthetic verb forms, the verb and subject are united in a single word, so that even one-word sentences are possible, e.g. _ga. "Tuigim" "I understand."

An example sentence:

If a nonfinite clause forms the complement of the verb, the verbal noun stands alone (without a preposition) in the clause.

with the two following sentences:

In the perfect tense, the passive voice is formed by using the passive participle with the existential verb.

The forms meaning "to be"

Irish, like Spanish and Portuguese, has two forms that can express the English verb "to be". The two forms perform different grammatical functions.

The existential verb _ga. "bí"

The existential verb is _ga. "bí". It is an irregular verb; see Irish verbs for its conjugation.

Existence, condition or location

This verb expresses the absolute existence of something, its condition, or its location. When accompanied by the adverb _ga. "ann" "there" it means "exist" or "there is/are". Otherwise,the verb is complemented by an adjective, an adverb or a prepositional phrase.

Definitions

A noun phrase alone cannot form the predicate of the existential verb. Instead, the noun complement is preceded by a form meaning "in my, in your, in his" etc.

Other examples of complex sentences using complementizers:
* _ga. Bhí faitíos roimhe "mar go" raibh sé taghdach. "People were afraid of him because he was quick-tempered."
* _ga. Ní chreidim é "cé go" bhfeicim é. "I don't believe it although I see it."
* _ga. Scríobh sí síos é "ar nós nach" ndéanfadh sí dearmad air. "She wrote it down so that she wouldn't forget it."
* _ga. Fan "nó go" dtiocfaidh sé. "Wait until he comes."

Conditional complementation

A conditional clause gives the condition under which something will happen. In Irish there are two kinds of conditional clauses, depending on the plausibility of the condition. The particle _ga. "má" introduces a conditional clause that is plausible, also called a "realis condition". _ga. "Má" causes lenition and takes the independent form of irregular verbs. Its negated form is _ga. "mura" and causes eclipsis. Preceding the preterite it is _ga. "murar" and causes lenition.

If the condition of the clause is hypothetical, also called an "irrealis condition" or "counterfactual conditional", the word _ga. "dá" is used, which causes eclipsis and takes the dependent form of irregular verbs. The negated equivalent is either _ga. "mura" or _ga. "murach go", meaning roughly "if it were not the case that...". The verb in both clauses is in the conditional.
* _ga. "Má" chreideann sé an scéal sin tá sé saonta go maith. "If he believes that story he is pretty gullible." (realis)
* _ga. "Murar" chaill sé é, ghoid sé é. "If he didn't lose it, then he stole it." (realis)
* _ga. "Dá" bhfágainn agat é ní dhéanfaidh tú é. "If I left it to you, you wouldn't do it." (irrealis)

Other examples of conditionals are:
* _ga. Éireoidh leis an bhfiontar "i gcleithiúnas go" mbeidh cách páirteach ann. "The venture will succeed provided that all take part in it."
* _ga. Tig leat é a bhriseadh "ar chuntar go" n-íocfaidh tú as. "You may break it provided that you pay for it."

Relative clauses

Direct relative

There are two kinds of relative clauses in Irish: direct and indirect. Direct relative clauses begin with the leniting relative pronoun _ga. "a" and the independent form of an irregular verb is used. The direct relative is used when the relative pronoun is the subject or direct object of its clause.
* _ga. D'imigh na daoine "a" bhí míshásta thar sáile. "The people who were unhappy went overseas."
* _ga. Sin í an obair "a" rinne mé. "That's the work that I did."

The direct relative is also used in topicalizations, e.g.:
* _ga. Is é Jimmy "a" chuaigh go Méiriceá. "It's Jimmy who went to America."

The direct relative is also used after the word _ga. "uair" "time":
* _ga. an chéad uair "a" bhí mé ann "the first time that I was there"

Indirect relative

Indirect relative clauses begin with the eclipsing relativizer _ga. "a" (in the preterite with leniting _ga. "ar"); the dependent form of an irregular verb is used. The indirect relative is used to signify a genitive or the object of a preposition. In these cases, there is a resumptive pronoun in the relative clause.
* _ga. an fear "a" raibh a dheirfiúr san ospidéal "the man whose sister was in the hospital" (lit. "the man that his sister was in the hospital")
* _ga. an fear "ar" thug a iníon céad punt dó "the man whose daughter gave him a hundred pounds" or "the man to whom his daughter gave a hundred pounds" (lit. "the man that his daughter gave him a hundred pounds")
* _ga. an seomra "ar" chodail mé ann "the room that I slept in" (lit. "the room that I slept in it")

The negative form of a relative clause, direct or indirect, is formed with the eclipsing relativizer _ga. "nach", or, before the preterite, with the leniting relativizer _ga. "nár".
* _ga. Sin rud "nach" dtuigim. "That's something I don't understand." (direct)
* _ga. bean "nach" bhfuil a mac ag obair "a woman whose son isn't working" (indirect; lit. "a woman that her son isn't working")

Sometimes a direct relative clause can be ambiguous in meaning, leaving unclear if the relative is accusative or nominative:
* _ga. an sagart "a" phóg an bhean "the priest who kissed the woman" or "the priest whom the woman kissed"

If the accusative reading is intended, one could use an indirect relative with a resumptive pronoun:
* _ga. an sagart "ar" phóg an bhean é "the priest whom the woman kissed" (lit. "the priest that the woman kissed him")

Wh-questions

A wh-question begins with a word such as "who, what, how, when, where, why" etc. In Irish, such questions are constructed as relative clauses, in that they can be constructed as either direct or indirect.

Direct relative wh-questions

Questions with "who, what, how many, which, when" are constructed as direct relative clauses.
* _ga. "Cá huair a" tharla sé? "When did it happen?"
* _ga. "Cé a" rinne é? "Who did it?"
* _ga. "Céard a" fuair tú? "What did you get?"
* _ga. "Cé mhéad" míle "a" shiúil tú? "How many miles did you walk?"
* _ga. "Cé acu" is daoire, feoil nó iasc? "Which is more expensive, meat or fish?"

Indirect relative wh-questions

Questions with prepositions (i.e. "on what?, with whom?") and questions with "why?" and "where?" are constructed as indirect relative clauses.
* _ga. "Cé aige a" bhfuil an t-airgead? "Who has the money?" (lit. "who with him is the money")
* _ga. "Cá leis ar" thóg tú an gluaisteán? "What did you lift the car with?" (lit. "what with it did you lift the car")
* _ga. "Cad chuige ar" bhuail tú é? "Why did you hit him?"
* _ga. "Cén áit a" bhfaca tú an bhean? "Where did you see the woman?"

Clauses introduced by "how"

There are two words for "how" in Irish: the word _ga. "conas" takes the direct relative clause, the phrase _ga. "cén chaoi" takes the indirect.
* _ga. "Conas a" tharla sé? "How did it happen?"
* _ga. "Cén chaoi a" mbaineann sin leat? "How does that concern you?/What business is that of yours?"

Complementary subordinate clauses in the form of a relative clause

Some complements in Irish take the form of a relative, in that they end in the relative particle _ga. "a"; both direct and indirect relative are found.

;Direct
* _ga. "Nuair a" bhí mé óg, bhí mé i mo chónaí i nDún na nGall. "When I was young, I lived in Donegal."
* _ga. Glaofaidh sí "chomh luath agus a" thiocfaidh sí abhaile. "She will call as soon as she gets home."
* _ga. Bhí sé ag caoineadh "an t-achar a" bhí sé ag caint liom. "He was crying while he was talking to me."
* _ga. Seinneadh port ansin, "mar a" rinneadh go minic. "Then a melody was played, as one often did ."
* _ga. Bhog sé a cheann "ar nós mar a" bheadh sé ag seinm. "He moved his head as if he were playing music."
* _ga. Tig leat é a choinneáil "fad is a" thugann tú aire dó. "You may hold it as long as you are careful with it."

;Indirect
* _ga. Lorg iad "mar ar" chuir tú iad. "Look for them where you put them."
* _ga. Fan "san áit a" bhfuil tú. "Stay where you are!"
* _ga. "An t-am ar" tháinig sé, bhíodar díolta ar fad. "By the time he came, they were all sold out."
* _ga. Inseoidh mé sin dó "ach a" bhfeicfidh mé é. "I will tell him that as soon as I see him."
* _ga. D'fhág sí é "sa gcaoi a" raibh sé. "She left it as it was."