A “copula” is a linguistic term for a small linking word connecting a subject to a predicative expression. In English, the copula is the verb “to be”: “Elrond is a man; Elrond is old”. In Quenya, the verb ná- may be used as a copula, but it is often optional. It is perfectly normal in Quenya to put the predicative expression immediately after the subject without any joining word at all: Elerondo nér; Elerondo yára. These expressions can be distinguished from normal adjective use because the adjective follows rather than precedes the noun: yára Elerondo “old Elrond” vs. Elerondo yára “Elrond [is] old”. As Tolkien described it:

An adjective following a noun, or if preceding separated from it (even by an article) was in Eldarin, and also in normal Quenya, predicative. So Q Sindar i Eldar Malariando “Grey are the Elves of Beleriand”; i rokkor rindi “the horses are swift”. In predicative use the adjective was inflected as the described noun (PE21/77-78).

As a copula “be, is” is not usually expressed in Quenya where the meaning is clear: sc. in such expressions as “A is good” where the adjective (contrary to the usual order in Quenya of a qualifying adjective) follows: the normal Quenya for this is A mára. But when the subject is not expressed, as usually in the impersonal “neuter”, e.g. “it is good” = “that is good, very well”, ná is used: so mára ná; also when it is postponed as in Galadriel’s Lament, Si vanwa ná, Romello vanwa, Valimar (PE17/93).

Thus ná is optional unless (a) the subject is displaced from its normal position before the predicate or (b) there is no explicit subject. The ná is also required with a pronominal subject suffix: úpa nas “he is dumb” (PE17/126), though in the same page Tolkien does seem to experiment with attaching the subject suffix directly to the predicate adjective: úpa-sse, úpa-nye “*he [is] dumb, I [am] dumb”. A third situation where ná becomes required is when it is in the past or future tense: i Eldar náner ataformaiti “The Elves were ambidextrous” vs. i Eldar ataformaiti “The Elves [are] ambidextrous” (VT49/7-8); hríve nauva urra “winter will be bad” (PE22/168).

The optional copula may be included, but when it is, it is usually displaced after the predicate: rokkor i Erulingaron máre nár “the horses of the Rohirrim are good” (PE22/166). Tolkien described it thus:

... hence lá karita i hamil mára alasaila (ná), “not to do (in this case) what you judge good (would be) unwise”. Q. needs no verb before alasaila but can add ná “is” (PE22/154) [As first written, this was mára (ná) alasaila, PE22/154 note #54].

Tolkien does not explain why the copula is displaced to the end, but it is my opinion that, in a phrase like Elerondo yára (ná), the optional ná could be added as an afterthought to emphasize that this phrase was, in fact, a “to be” statement. The more complex the phrase, the more likely it is that the ná will be added, as with lá karita i hamil mára alasaila (ná) given above. This pattern became the norm and eventually a grammatical rule.

In the past or future tense the verb ná- generally appears in the normal position in between the subject and its complement, as in Eldar náner ataformaiti or hríve nauva urra given above. There are also examples of aorist ná appearing in the middle of complex phrases where its presence reduces ambiguity: A (ná) calima lá B “A is brighter than B” (PE17/90). So perhaps “a well loved man is a happy man” would be mai melda atan ná alassea atan, or “nine times two is eighteen” = nerte yullume ná tolque.

The na can also appear at the beginning of a phrase when used as an impersonal imperative: na care indómelya “thy will be done, *(lit.) be done will-thy”; na aire esselya “hallowed be thy name, *(lit.) be hallowed name-thy” (VT43/12). This, however, is probably just a reduced variant of the proper imperative á na, as in á na márie “be well” (PE17/162) vs. na márie > namárie “farewell, (lit.) be well”.

The verb ná- can be used together with the dative in certain formulaic expressions describing the emotional state of a person: nás mára nin “it is good for me” meaning “I like it” (VT49/30); náne márie nin “it was well to me” meaning “I was glad” (PE22/158). Whether this was used only in a few expressions or was a more general pattern isn’t clear.

The verb ná- is the simplest way to express “yes” in response to questions about facts (PE22/166): “Are the horses of the Rohirrim good?”; ná “yes, (lit.) it is”, with slightly more emphatic variant nása “it is so”. It is not used to answer questions of opinion or requests, however, which instead use sá (†þá) “yes, I agree, I will” (PE22/166), as in: “Do you like this? Will you help me?”; sá.

The verb ná- is not the only Quenya verb for “to be”. There is also ea- “to be, to exist”. Tolkien described the difference between those two verbs in Late Notes on Verb Structure written in 1969:

Stem of verb “exist” (have being in primary world of history) was √EŊE, distinct from √NA joining adjs./nouns/pronouns in statements (or wishes) asserting (or desiring) a thing to have a certain quality, or to be the same as another. eŋe is not followed by any adj. or noun but only by a[n] adverb (or negated adverb) mainly[?] of time. Present continuous of √EŊE is ëa “It exists” (PE22/147).

Verb nā- is used to assert qualities etc. of separate things in the Universe, verb eŋa (ëa) to assert their actual real existence extra-mentally (PE22/166 note #113).

Thus ná is used for describing the qualities of a thing: “A is B”, whereas ea is used for statements about its actual existence within the universe: “A exists”. There are also examples of ea being used with a prepositional phrase or adverb:

• Átaremma i ëa han Eä “our Father who art in Heaven” (VT43/12).
• i Eru i or ilyë mahalmar ëa tennoio “the One who is above all thrones forever” (UT/305).

A more literal translation of the above would be: “our Father who exists beyond existence” and “the One who above all thrones exists forever”.

Statements of Tolkien’s from late 1940s indicate that a more specific verb than “is” would often be used to describe locations:

Generally also the verb “be” was omitted in questions and statements concerning location, or if a verb was required one proper to the precise circumstances was employed, as “be found, lie, stand, dwell etc.” (PE22/123).

Where “is, be” refers to location = be placed, found, is to be had; or to stay, remain, abide, be situated dwell, etc. then various verbs of more precise and particularly applicable senses can be used, and usually are (PE22/125).

Thus it seems the normal practice in Quenya was to use alternate verbs like mar- “dwell” to express location: Elerondo mare Imladrisse “Elrond dwells in Rivendell”. However, if you do want to just use “is”, I currently believe that ná would be used for this purpose: Elerondo Imladrisse (ná).

For more information on the conjugation of the verbs ná- and ea- as well as the conceptual development of the verbs themselves, see the entry on irregular verbs.

Conceptual Development: In earlier periods of Quenya’s conceptual development, other verbs were used for “to be” expressions, as discussed in the entry on irregular verbs. These earlier verb forms tended to put the verb in the usual position between the subject and its complement; the displacement of the copula after the predicate seems to be a relatively late idea. However at various points Tolkien used a special “stative” construction that suffixed the “to be” verb directly to the predicate adjective; see that entry for further discussion.

The idea that the copula was optional, however, dates at least back to the late 1940s; in this conceptual period, Tolkien used ye >> ea as the general verb for “to be”:

Identity was normally expressed by apposition alone. For example: Eldar Alphírimor: “Elves are Immortals”. Since the normal place of an adjective attributive was in Q. before its noun, an adjective was marked as predicative by being placed after the noun: Eldar alphírimar [“Elves are immortal (adj.)”]. Such an adjective was inflected (for number) (PE22/124).