lojban tutorial

By Xah Lee. Date: .

This is my personal learning notes on lojban. I intent to make it a polished tutorial, but it barely began and was never complete. Wikipedia would probably be a better resource.

Lojban Alphabets

Lojban uses the following letters and symbols as its alphabet:

' , . a b c d e f g i j k l m n o p r s t u v x y z

There's no {h, q, w}. The apostrophe ' and period . symbols are part of lojban alphabet, they are not punctuations. Lojban language does not need it.

How to read lojban

Lojban Readings is similar to English Readings.


Like English's father, papa, far, darling

canja ⇔ trade
bajra ⇔ run
taxfu ♪ ⇔ clothing;


Like English's bet, desk, pet.

vecnu ⇔ buy/sell


Like English's green, bean, beam, beast, ease

fagri ⇔ fire
spati ⇔ plant


Like English's joke, boat, toe


Like English's boot, shoe, shoot

y  sofa, above lobypli /LOB,uh,plee/
y                   the h in hello, or a in about and around.
'     h
c  SHirt, SHoe
b    bottle, best, better
d    dance, dad, dead
g    goose, god, get, pig, dig
v    voice, vote, save
z    zinc, dizzy, jazz

j  'dg' sound, as in meaSUre

f  fall, fast, if
k  kiss, kick
p  power, jump, hope
s  sell, song, piss
t  time, take, hit

l  late, laugh, doll
m  move, more
n  nose

r  rock
x  a vocal h sound, like the ch in Bach or Loch Ness monster

Type of Words

Lojban words are only of the following 3 types:

cmene: names (people's names, places's names).

brivla: a word that acts like a function (mostly like verbs in English)

cmavo: structure words (and, or, at, with, of, by, to, is, nor, for, hereby, …)

cmene are just names. People's names, places's names. These are necessary in every language.

brivla are function words. They are functions like programing languages, as in do_something(arg1, arg2, arg3, …). Each function word has a associated definition. For example, “i run home” would be like “run(I, home)”. “I want to eat bread” would be something like “want(I, abstract(eat(none, bread)))”. All lojban sentences are composed of functions like that.

Since lojban is not a programing language, it does not actualy use commas and parenthesis or nesting as in printed code. These are not suitable for verbal communication. Instead, lojban has many little words that functions like these technical punctuations to connect lojban sentence into a logical structure. These little words are called “cmavo”. In natural languages, it is like words like “and, or, at, with, of, by, to, hereby, for, too …”. Their purpose is to connect words in various ways to make meanful sentences. Lojban has about a hundred cmavos of many different types for different purposes.

Some are logical connectives like programing language's “and, or…” that are meaningful to the content of a sentence. Some are word or sentence connectors such as English's “and …; but …”. Some acts like parenthesis to demarcate lojban's language structure. Some acts like attitude indications such as English's “ah, god, ha, hey, bah!…”… there are many types of these cmavos in lojban.

In summary, lojban has 3 types of words: cmene (names), brivla (function words), and cmavo (little grammar words) Lojban sentences are compositions of functions, demarcated by cmavos.

Cmene always end with a consonant followed by a mandatory pause (a period). No other Lojban word ends with a consonant. Thus names are easily recognized by its form. Name must also start with a consonant. Here are some examples of cmene: “.alis.” (Alice), “teris.” (Teris game), “djan.” (John), “romas.” (Rome), “beidjin.” (Beijing).

Brivla are always 5 letters. Examples of brivla: ckire (thank), sidju (help), citka (eat), zdani (home/house).

brivla are of 3 types:

bridi is a predicate function. (brivla means words that is bridi) Sumti is argument.

Lojban Sentence Structure

All Lojban sentences have this structure:

argument1 function_word argument2 argument3 …

where any of the arguments is a word or sentence.


le prenu   cu klama      le zdani        le briju       le zarci        le karce
person      goes (to)     house      (from) office   (via) market  (using) car.

In this example, “klama” is the main brivla (briva ⇔ functional word). The definition of a brivla has the form “x1 briva_name x2 x3 …” corresponding to a functional notation like “briva_name(x1, x2, x3, …)”. For example, “klama” means come/go, and its definition is given as:

klama ≔ x1 comes/goes to destination x2 from origin x3 via route x4 using means/vehicle x5

So, if i say “I klama your house my house my car”, it would mean “I go to your house from my house by my car” or more naturally “I drive my car from my house to your house”, and in functional notation it would be “klama(I, your house, my house, my car)”. The “I, your house, my house, my car” are the parameters. The actual words/sentences used to fill in the parameters are called arguments, or parameter values. Arguments is called “sumti” in lojban.

Remember that all lojban words (except names (cmene) and grammar words (cmavo)) are defined as function and its parameters. The definition gives meaning to the function word, and meaning for its parameters, and how the function word relates to the parameters, and all lojban sentences have the structure “x1 function_word x2, x3, …” where any of the parameters is a word or other sentences.

In this example:

le prenu   cu klama      le zdani        le briju       le zarci        le karce
person      goes (to)     house      (from) office   (via) market  (using) car.

The parameters of klama are filled in with five specific sumti values:

x1 → le prenu (the person)
x2 → le zdani (the house)
x3 → le briju (the office)
x4 → le zarci (the market)
x5 → le karce (the car)

?? The definition of the brivla used above, klama, shows this relationship. There are five places labelled x1 through x5. The brivla itself describes how the five places are related, but does not include values for those places. In this example, those places are filled in with five specific sumti values:

?? x1 contains le prenu (the person) x2 contains le zdani (the house) x3 contains le briju (the office) x4 contains le zarci (the market) x5 contains le karce (the car)

It would be clear if we simply write in a functional notation “f(x1,x2,x3)”. However, this writing system is not suitable as a human language. For example, when speaking it, one would say “f left parenthesis x1 x2 x3 right parenthesis” makes it very difficult to interpret. For example, if the sentence is complex, such as “f(f2(y1,y2),x2,g(h1,h2,h3))”, it becomes impossible to understand it by ear and interprete the levels of nesting, even though it is very clear visually.

For this reason, lojban does not really use parenthesis or similar markers as part of its language. Instead, it takes the form of “x1 f x2 x3 x4 …”. And certain other ways becomes necessary to mark the beginning or ending of arguments. For example, note the word “cu” in the above klama example. “cu” is a cmavo in lojban to indicate that it is the end of the first argument.

some clarification between confusing terms of brivla, selbri, bridi:

A Lojban sentence expresses a relationship (bridi), normally claiming that the relationship holds (that it is 'true'). A bridi relationship consists of several ideas or objects called arguments (sumti), which are related by a predicate relation (selbri). The following uses the Lojban terms bridi, sumti, and selbri, because it is best to come to understand them independent of the English associations of the corresponding words.

source: file:///Users/t/na_vajni/skami/bangu/lojban/lojban.level0.html.utf%20Folder/diagsumm.html#sent

The simplest form of selbri is an individual word. A word which may by itself express a selbri relation is called a brivla. The three types of brivla are gismu (root words), lujvo (compounds), and fu'ivla (borrowings from other languages). All have identical grammar; they are allowed wherever "selbri" appear in these examples.

Some short words may serve as selbri, acting as variables that stand for another selbri. The most commonly used of these is go'i, which represents the main bridi of the previous Lojban sentence, with any new sumti or other sentence features being expressed replacing the previously expressed ones.

source: file:///Users/t/na_vajni/skami/bangu/lojban/lojban.level0.html.utf%20Folder/comp.html

-- (bridi=relationship. selbri=predicate relation. brivla: predicate.)

-- tanru: metaphor; a sequence of gismu; compounded selbri | mi sutra klama la meris. (Example: i quickly-go to Mary)

selma'o: parts of speech

• mi| I/me/my, we/us/our
• do| you/your
• ti| this/this-here/this one, these/these here/these ones
• ta| that/that-there/that one, those/those ones
• tu| that yonder, those yonder

lojban cmavo

• cu | separator between sumti and selbri. Used before the selbri.
• vau | indicate that no more sumti follows. Place near the end.
• zo'e | place holder for a unspecified sumti. (used when a sumti is unimportant or obvious)

Asking Questions

• xu | true/false clause. Placed after a sumti or selbri to question the true/false of it. Place in the beginning to question the whole bridi. Note: vau must be used if xu is placed at the end of a sentence.

todo See file:///Users/t/na_vajni/skami/bangu/lojban/lojban.level0.html.utf%20Folder/diagsumm.html#sent

• ma | place holder for an unknown sumti, making it a question. | Examlpe: do klama ma ⇔ you go where? | Example: ma tavla ma (who talks to whom?)

• mo | place-holder for unknown selbri, in a way of asking a question. | Example: do mo la klaudias. ⇔ you what Claudia?

lojban pronoun sumti

• ri | he/she/it (the-last-referenced-sumti) | mi [cu] tavla fi la lojban. ri (i talk about lojban in lojban)
• ko | 'you' in a command form; imperative. | ko tavla mi (talk to me) | mi tavla ko (let me talk to you.)
• go'i | a variable that refers to the previous bridi. | mi go'i (me (something) too)
• ko'a | it/he/she/they (a specific value)
• di'u | it/this (the last sentence)

• ni.o | indicates the beginning of a paragraph. Used at the beginning of a sentence.
• .i | indicates the beginning of a sentence. Used at the beginning of a sentence.

• la | place in front of cmene (names). Example: la Mari.
• le | article; turn a selbri into a sumti; adding ku at the end if necessary | Example: le cukta [ku] (a book) | description sumti ("le selbri [ku]") | mi [cu] tavla le vecnu [ku] ⇔ i talk to the seller.
• ku | the closing marker for le.
• li | article for numbers. • lu | quotations, which begin with “lu”, “le'u”, “zo”, or “zoi”| Example: mi cusku lu e'osai li'u le tcidu. (I express “Please!” to-the reader)

le  LE  the, the one(s) described as
lo  LE  some, some of those which really are
la  LA  the one(s) named
ku  KU  elidable terminator for LE, LA


• .e'o | please; polite mode indicator (polite attitudinal) | Example: .e'o ko dunda le cukta mi (please you give book me)


• na | negate a bridi; contradictory negation ("na selbri") | Example: mi cu na nelci la bil. (i don't like Bill)

• ja'a | the opposite of na. | mi na klama ti ta .i mi ja'a go'i (it's false that i go to this from that, it is true that i do (go to this from that))

na deals primarily with the truth or falsity of a bridi. Lojban also supports a separate form of negation, called contrary or scalar negation. A scalar negation attaches tightly to the next brivla of the selbri, modifying the meaning of the word on some scale. Scalar negation structures may appear anywhere where a brivla or selbri is allowed. Scalar negation words include na'e (other-than), to'e (absolute opposite-of), and no'e (neutral on the scale); je'a is a strong positive scale assertion, translating roughly as 'certainly' or "indeed":


mi melbi (i'm beautiful) mi je'a melbi (i'm indeed beautiful) mi no'e melbi (i'm neutral on the beauty-ugly scale) mi na'e melbi (i'm other-than beautiful) mi to'e melbi (i'm opposite of beautiful)

• pe | possesive | la karce pe la meiris. (Mary's car). | or, place the possesor between the article and object, Example: "le la meiris. karce" (Mary's car)

po | a more strong form of possessive than pe, may indicate unique posession or owership. | Example: "le cukta po mi" (my book)

po'e | a permanent form of possessive. example: le birka po'e la klaudia (Claudia's arm) (alienable possession and inalienable possession)

1 pa 2 re 3 ci 4 vo 5 mu 6 xa 7 ze 8 bi 9 so 0 no

ro | each/all so'a | almost all so'e | most so'i | many, lots so'o | several so'u | few

su'e | at most su'o | at least

• ki'o | comma separator for numbers. | Example: 1,590 is read as "pa ki'o musono". mupici | fraction separotor used for numbers. (period) | 4.27 is vo mupici reze.

• li | article for numbers. | Example: li pamuxa (156)

• lo | article | ci lo nanmu cu bevri le pipno ((all; there have been) 3 men carried the piano) | ci lo gerku cu batci mi (three dogs bite me.) lu'o | a group of | lu'o ci lo nanmu cu bevri le pipno (3 men carried the piano) | lu'o ci lo gerku cu batci mi (3 dogs bite me) | le pano ninmu (3 women) | lu'o le pano ninmu (3 women as a group) • lei ⇔ lu'o le • loi ⇔ lu'o lo

• moi | ordinal numbers | Example: le tavla [ku] cu ci moi [vau] (the talker is third) • mei | cardinal numbers | Example: le tavla ku [cu] ci mei [vau] (the talkers are a-threesome) • si'e | potional numbers "le blari'o ku [cu] pimu si'e [vau]" (The blue-green (things) are half.)

• cu'o | probability numbers

pi'e | the period, part of | Example: li papa pi'e mu (5 past 11) | Example: li papa pi'e mu pi'e pabi (11 (o'clock), 5 (min) 18 (sec))

• nu | "event" abstraction descriptor; grammatically: it turns a whole bridi into a selbri, and adding le in front of the selbri, it becames a sumti. The elidable end marker for nu is kei.

Example: la djan. cu nu sonci kei djica
    John is-an-(event-of being-a-soldier) type-of desirer.
    John wants to be a soldier.

What nu does here is allow us to put a whole bridi into a selbri place, and by extension (if we put an article in front of it) a sumti place. | Example: "mi klama" is a bridi. "nu mi klama" is selbri. "le nu mi klama [ku]" is a sumti.

• ni | amount • ka | quality; property


• go'i

Some short words may serve as selbri, acting as variables that stand for another selbri. The most commonly used of these is go'i, which represents the main bridi of the previous Lojban sentence, with any new sumti or other sentence features being expressed replacing the previously expressed ones. Thus:

ta [cu] go'i [vau]

That too/same-as-last selbri.

• be | the beginning marker for internal tanru: "brivla/selbri be sumti [bei sumti][bei sumti] … [bei sumti] [be'o]"
• bei | see "be".
• be'o | see "be".


9.1)  la djan. klama le zarci
    John goes-to the market.

you may retort:
 la djan. go'i troci
    John [repeat last] are-a-tryer
    John tries to.

Example 9.2 is short for:
9.3)  la djan. klama be le zarci be'o troci
    John is-a-goer (to the market) type-of trier.

Example: ta [cu] ( (tavla (be do) (bei (le melbi ku)) [be'o]) vecnu) [vau] Basic skelecton: ta tavla vecnu (that talking salesman) the tavla is modifed to be "talking to you about beautiful things". So, complete translation would be: That's a salesperson who talks to you about beautiful things.

Example: ta [cu] (tavla) (be do) (bei le melbi vecnu ku [be'o]) [vau] That (one) talks to you about a beautiful salesperson.

source: lojban.level0.html.utf%20Folder/comp.html

time indicator, tenses.

• pu: past. used before brivla: Example: "(la djan. pu klama le zarci)" ⇔ djan went to store

• ca: present. Example: la djan. ca klama le zarci ⇔ djan go to store (now)

• ba: future.

• vu: to indicate far away. "do [cu] vu vecnu zo'e" ⇔ you yonder sell.

le pu bajra [ku] cu tavla ⇔ The earlier/former/past runner talked/talks.


17.9) le vi tavla [ku] cu ba klama ---------------- ======== The here talker [future] goes. The talker who is here will go This talker will go.

see http://lojban.org/publications/reference_grammar/chapter2.html

tanru grouping and connectives

tanru are left-grouped by default. Example: “cmalu nixli ckule” ⇔ “(cmalu nixli) ckule” ⇔ “cmalu bo nixli ckule”.

• bo | short scope link, short scope joiner; joins various constructs with shortest scope and right grouping. Example: “cmalu nixli bo ckule” = “cmalu (nixli ckule)” = “small girl-school” = “cmalu bo nixli bo ckule”.

• ke| start grouping; start grouping of tanru. It functions like a left parenthesis. It's terminator is “ke'e”, which functions like a right parenthesis. Example: “cmalu bo nixli ckule” ⇔ “ke cmalu nixli ke'e ckule”. Example: “ta melbi ke cmalu nixli ckule ke'e”.

• je | tanru and logical connective; and. Example: barda je pelxu bo xunre gerku = barda je ke pelxu xunre ke'e gerku = big and yellowish-red, dog.

• ja | like je, but means “or”.

• joi | is the kind of “and” that denotes a mixture. | Example: ti blanu joi xunre bolci ⇔ this (mixed (red and blue)) ball.

see http://lojban.org/publications/reference_grammar/chapter5.html

pei zo ksax cmene?

pei CAI emotion ? attitudinal: attitudinal question; how do you feel about it? with what intensity? zo ZO 1-word quote quote next word only; quotes a single Lojban word (not a cmavo compound or tanru)

Spatial words of distance and direction. used in front of bridi. e.g.

le nanmu va batci le gerku
The man [medium distance] bites the dog.
Over there the man is biting the dog.
vi  VA  short distance
va  VA  medium distance
vu  VA  long distance

zu'a    FAhA    left
ri'u    FAhA    right
ga'u    FAhA    up
ni'a    FAhA    down
ca'u    FAhA    front
ne'i    FAhA    within
be'a    FAhA    north of