Beyond the level of syntax is discourse. This is the influence that the practical requirements of speech have on grammar. Such influences include the relative frequency of words and phrases; context, mutual knowledge, and the flow of information in a conversation; and the intentions and feelings of the speakers. For example, the choice between long and short case forms and long and short plural forms may depend on such factors; other areas of grammar influenced by discourse factors include the choice between preposition and suffix; "free" word order; the choice between referring to something with a noun or with a pronoun; the omission of pronouns, tense, aspect, and mood when these are assumed to be understood; the choice between using the topic or a grammatically determined case for a noun phrase; the use of second-position (affect) infixes in a verb; and the transitivity of the verb.
Various particles in Na’vi are used for addressing people, expressing emotion, and organizing a conversation. For example, tse is used to introduce an utterance, a mild announcement that one has something to say, like "now" or "well" in English. Tut is a particle of continuation; if someone asks for your name, or how you are, after answering you can add ngaru tut? "and you?"[note 1] The vocative particle ma was covered in the chapter on nouns, and the question-tag particle srake in the chapter on questions. Also considered particles are interjections such as tewti! "wow!", though other parts of speech may be used in this fashion, such as tam "to suffice" or "okay".
The second-position infixes, covered in the chapter on verbs, are determined primarily be discourse phenomena: The emotional connection the speaker has with the event, how likely the statement is to be accurate, and how much respect the social situation calls for.
There are also emotive particles that appear at the end of a clause and reflect the emotional connection the speaker feels about the topic of discussion or with the audience:
- Disparaging pak, as in Tsamsiyu pak? "Hah! A warrior! (you call that a warrior?)"
- A particle for surprise, exclamation, and encouragement, nang "oh my!", which typically occurs with nìtxan "so much", as in sevin nìtxan nang! "my aren't you pretty!" or "look how pretty you are!"
- A particle ko which elicits agreement, like the eh of Canadian English (in other English dialects, ko can be translated "let's", "okay?", "why don't you", "wouldn't you agree?", etc.), as in makto ko! "Let's ride!" and,
- Tsun tutet tspivang ko
- "They can kill a person, you know."
Omission of pronouns
Pronouns allow one to refer to something multiple times without repeating its name. However, Na’vi goes a step further: Pronouns tend to be used when switching from one referent to another, but otherwise dropped. That is, once the identity of a referent is established, pronouns aren't necessary, even for the subject of a clause. This is familiar from English texting, but is not as common in conversation.[note 2] In Na’vi, it is good conversational style as well. The identity of subjects may also be recovered from situational expectations. If a simple statement of a feeling is made, such as ’efu ngeyn "feel(s) tired", it can be assumed that the subject is the speaker, oe, as one can only be sure of one's own feelings; and if a question, ’efu ngeyn srak?, it can be assumed that the speaker is inquiring about (ay)nga "you", as you're the only one whose feelings you would know directly. For third persons, one would normally expect the evidential in ‹ats›, as one can have no direct knowledge of the feelings of another person: ’efatsu ngeyn "(s/he) seems tired"; ’efatsu ngeyn srak? "do (they) seem tired (to you)?".
Two language registers are attested in Na’vi. The formal ceremonial register has already been introduced; it's characterized by formal pronouns and an infix to the verb. There is also a military register. This is characterized by clipped speech—clipped even by Na’vi standards—and abbreviated pronouns. For example,
- Tìkan tawnatep!
- "Target lost!"
T‹awn›atep cannot function as an English passive; the closest in the normal register would be tìkan atawnatep "a lost target".
In addition, the ä is dropped from genitive pronouns: oey (pronounced [wey]) "my", ngey "your", pey "her/his", etc.
As was discussed in the section on case, Na’vi frequently uses a topic–comment structure, where a phrase is placed at the beginning of the sentence as the topic (background) for the comment which follows:
- Sìpawmìri oe ngaru seiyi irayo
- "Thank you for the questions" (lit. "As for the questions, I thank you")
However, a noun phrase is sometimes moved to the front of a clause without it taking the topic case:
- Fìswiräti, ngal pelun molunge fìtseng?
- "This creature, why do you bring him here?"
fì-swirä-ti nga-ìl pe-lun m‹ol›unge fì-tsenge this-creature-acc you-erg what-reason bring‹pfv› this-place
Since the topical case can only be used with nouns, in order to topicalize a clause, it must be relativized to a dummy noun:
- Furia nì'Ìnglìsì pamrel sivi, oeru txoa livu.
- "Excuse me for writing in English."
fì-’u-ri-a nì-’Ìnglìsì pam-rel s‹iv›i oe-ru txoa l‹iv›u this-thing-top-attrib adv-English sound-image make‹sjv› I-dat pardon be‹sjv›
(Lit. "as for writing in English, may I be forgiven".)
- expand 'focus'
Na’vi constituent order (subject–object–verb order) is syntactically free—that is, it is determined by discourse factors rather than by syntax. The word order within a noun phrase (demonstrative-numeral-adjective-noun etc.) is similarly free. One of the few cases where a set word order is common is that lu tends to come at the beginning of a clause when it is used without a subject to mean "there is", a construction used for "to have": Lu oeru ikran "I have a banshee".
The basic (least marked) order is perhaps subject before object. Moving an argument to the front of a clause can be used to focus on it. For example,
- Na’vil ayyerikit yom "The People eat hexapedes"
- Ayyerikit Na’vil yom "Hexapedes (not direhorses) are eaten by the People"
That is, "hexapedes" are the point of the statement. (Na’vi does not have a passive voice, which may perform a somewhat similar function in English.) This is the opposite of the topic, which would set the hexapedes up as the background for a following point:
- Ayyerikìri, Na’vil yom "As for hexapedes, the People eat them."
Likewise, moving an argument from where it would be expected at the front of a clause to the end may give it more "punch":
- Lu oeru kxetse "I have a tail" (neutral statement)
- Ngeyä kxetse lu oeru "Your tail is mine!" (emphasis on mine)
As noted under dative case in the chapter on nouns, the default word order of possession is lu "be" followed by the possessor in the dative, as in lu oeru "I have". Along with context, this helps distinguish who is who in a multiple dative construction:
- Lu oeru aylì’u frapor.
- "I have something (= words) to say, to everyone."
where frapor "everyone" can be understood to be the recipient because it is not adjacent to the verb.
Another factor in Na’vi word order is aesthetic. For example, nga yáwne lu oér "I love you" (lit. "you are beloved to me") has the order it does because it is considered the most euphonious.
In proverbs and songs, meter is also a consideration. For example, in the korén a’áwve tìruséyä ’awsiténg ("the first rule of living together", AKA the Golden Rule):
- Hém ngeyä zénke fkóru livú,
- tsáhem a ngáru pŕrte’ ke lú [note 3]
This kind of subordinating strategy is common among human fixed-order verb-final languages such as Japanese, Korean, and Turkish. Indeed, though these examples followed the English word order of subordinate clause following the noun it modifies, the human verb-final order of subordinate clause preceding the noun is also possible in Na’vi:
- Tsun oe ngahu nì-Na’vi pivängkxo a fì’u oeru prrte’ lu.
- "It’s a pleasure to be able to chat with you in Na’vi."
tsun oe nga-hu nì-Na’vi p‹iv›ängkxo a fì-’u oe-ru prrte’ lu be.able I.intr you-with adv-Na’vi chat‹sjv› sbrd this-thing I-dat pleasure? be
- (Lit. "this being-able-to-chat-with-you-in-Na’vi thing is a pleasure to me")
For example, "I didn't see where she was going", po tsane karmä a tsengit ke tsìme’a oel above, could also be worded oel tsìme’a ke tsengit a po karmä tsane, where po karmä tsane "she was going there" occurs on either side of the object tsengit "place". This contrast can be further seen in the following, where a relative clause is used to nominalize a clause in order for it to form a topic:
- Ngal oeyä ’upxaret aysuteru fpole’ a fì’uri, ngaru irayo seiyi oe nìtxan!
- "Thank you very much for sending my message to people!"
nga-l oe-eyä ’upxare-t ay+tute-ru fp‹ol›e’ a fì-’u-ri nga-ru irayo s‹ei›i oe nì-txan you-erg I-gen message-acc pl+person-dat send‹pfv› sbrd this-thing-top you-dat thank do‹approb› I.intr adv-much
- Furia ngal oeyä ’upxaret aysuteru fpole’, ngaru irayo seiyi oe nìtxan!
fì-’u-ri-a nga-l oe-eyä ’upxare-t ay+sute-ru fp‹ol›e’ nga-ru irayo s‹ei›i oe nì-txan this-thing-top-sbrd you-erg I-gen message-acc pl+person-dat send‹pfv› you-dat thank do‹approb› I.intr adv-much
"Because" for the English clause order (verb-X because verb-Y) is either taweyk(a) (from oeyk "cause") or talun(a) (from lun "reason"). With the opposite clause order, the forms switch to aweykta and alunta.
Verbs in which transitive and intransitive forms imply different agents are made transitive with the causative infix ‹eyk›. For example, latem means "change", as an object changes by itself, as say the seasons change; if an external agent causes the change, however, the form is l‹eyk›atem. Similarly sngä’i is "begin" in the sense that something happens on its own, as the rain begins; with an external agent, as in "I began work", the form is sng‹eyk›ä’i. However, with many verbs, transitivity does not imply a change in the acting agent. For example, pey may be either "wait" (intransitive) or "await" (transitive):
- Nìaynga oe perey nìteng.
- "Like you, I too am waiting."
- Oe tsun pivey trrit a nga tayìng ayoer(u) nì'ul.
- "I can await the day when you will give us more."
oe tsun p‹iv›ey trr-it a nga t‹ay›ìng ay-oe-ru nì-’ul I can wait‹sjv› day-acc sbrd you give‹fut› pl-I-dat adv-more
Here the person waiting is the same, regardless of the transitivity of the verb, so the causative infix is not used.
General action, without any specific object, as in English "I ate too much", is intransitive, whereas an implied but unstated object, as in "he ate some (of it)", is transitive.[note 4] Thus,
- Oe taron
- "I hunt"
oe taron I.intr hunt
Here the speaker is merely saying that hunting is an activity that they engage in; this equivalent to such intransitive clauses as "I walk". An overt object, on the other hand, requires that the agent be in the ergative case:
- Oel tolaron pa’lit
- "I hunted a direhorse"
If, however, the agent is in the ergative case, but there is no expressed object, then an omitted object is understood. So if asked about yerik, the speaker might say,
- Taron oel kop.
- "I hunt them too"
taron oe-l kop hunt I-erg as.well
In the case a relative clause removed either the subject or object of a dependent clause, the case of the other, and the transitivity of the dependent verb, are unaffected:
- Ikran a tolaron oel tsawl lu nìtxan.
- "The banshee I hunted was very big."
Here ikran is in the intransitive case because it is the subject of lu "to be"; however, oel remains in the ergative, since the object is understood from the context: Ikran a tolaron pot oel tsawl lu nìtxan "the banshee which I hunted it was very big".
The ergative case can also be dropped if the object is retain in a non-accusative case, as in a topic:
- Tìfyawìntxuri oeyä perey aynga nìwotx.
- "You are all waiting for my guidance."
With an intransitive verb, the causative simply makes the verb transitive. For example, from po holahaw "he.INTR slept" we get oel h‹eyk›olahaw poti "I.ERG put him.ACC to bed (made him sleep)". However, if the verb is already transitive, its subject (now the 'causee') becomes dative rather than accusative. That is, there may be up to three arguments, in the ergative, dative, and accusative cases. So, from Neytiril yerikit tolaron "Neytiri.ERG hunted a hexapede.ACC, we get:
- Eytukanìl Neytiriru yerikit teykolaron.
- "Eytukan had Neytiri hunt a hexapede."
Not all arguments are required; also, the causee can be included but made more peripheral by putting it in an adpositional phrase:
Eytukanìl yerikit teykolaron. Also: Eytukanìl fa Neytiri yerikit teykolaron. "Eytukan had a hexapede hunted." "Eytukan had a hexapede hunted by Neytiri." eytukan-ìl yerik-it t‹eyk›‹ol›aron (name)-erg hexapede-acc hunt‹caus›‹pfv› eytukan-ìl fa neytiri yerik-it t‹eyk›‹ol›aron (name)-erg by (name) hexapede-acc hunt‹caus›‹pfv›
In English, the opposite of a causative is a passive. Na’vi does not have passives; something like "hexapedes are eaten" would be worded fkol yom ayyerikit "one eats hexapedes", with the pronoun fko "one". The difference between "hexapedes are eaten by the People" and "the People eat hexapedes" is essentially one of word order; since Na’vi word order is free, it can be changed without having to change the verb or the subject, as noted above.
- In both questions, the dative case is used.
- For example, "Saw you online and wanted to say hi. Hope everything is fine. Will try to call this week. BTW, Carol finally got in touch with me. Said she's been very busy. Didn't go to India after all. Went to Vegas instead. I can't figure her out. Guess she decided on gambling rather than the guru." Note that "I" and "she" are required when changing from Carol to the speaker and then back to Carol, but otherwise not much bothered with.
- Lit., "Your actions must not be to one (= another), those which are not a pleasure to you"
- A clause in which an erstwhile transitive verb behaves intransitively, with no argument in the ergative or accusative case, is called an anti-passive.