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Tenses 1

How unfamiliar a language like Lojban must seem to an English-speaker, when one can read through eleven lessons of Lojban grammar without meeting a tense once! This is because, unlike many natural languages (most Indo-European ones, for instance), all tenses in Lojban are optional. Saying mi tavla do can mean "I talk to you" or "I talked to you" or "I always talk to you" or "In a moment, I will have just finished talking to you", among other possibilities. Context resolves what is correct, and in most conversation, tenses are not needed at all. However, when it's needed it's needed, and it must be taught. Furthermore, Lojban tenses are unusual because they treat time and space fundamentally the same – saying that I worked a long time ago is not grammatically different than saying I work far away to the north.

Like many other languages, the Lojban tense system is perhaps the most difficult part of the language. Unlike many other languages though, it's perfectly regular and makes sense. So fear not, for it will not involve sweating to learn how to modify the selbri or anything silly like that.

No, in the Lojban tense system, all tenses are sumtcita, which we have conveniently just made ourselves familiar with. Okay okay, technically, tenses are slightly different from other sumtcita, but this difference is almost insignificant, and won't be explained until later. In most aspects they are like all other sumtcita.

There are many different kinds of tense-sumtcita, so let's start at the ones most familiar to English-speakers.

pu sumtcita: before SUMTI.

ca sumtcita: at the same time as SUMTI.

ba sumtcita: after SUMTI.

These are like the English concepts before, now and after. In actuality though, one could argue that two point-like events can never occur exactly simultaneously, rendering ca useless. But ca extends slightly into the past and the future, meaning "just about now". This is because human beings don't perceive time in a perfectly logical way, and the Lojban tense system reflects that.

Let's look at a few examples:

Sentence Possible translation
mi pu dunda lo mlatu I donated the cat.
ca ku mi vecnu lo skami I am selling the computer.
mi ba gleki I will be happy.
mi tavla lo ba ctuca I am talking (or have talked or will talk) to the future teacher.

Usually when speaking, we do not need to specify which event in the past this action is relative to. In "I donated the cat", we can assume that the action happened relative to now, and thus we can elide the sumti of the sumtcita, because it's obvious. In the second example, "I am selling my computer", we did the same thing, albeit with slightly different syntax. Recall that there are two ways to leave the sumti of sumtcita unspecified: either put it before the selbri, or terminate it with ku.

In these cases, the sumti which fills the sumtcita is an implied zo'e, which is almost always understood as relative to the speaker's time and place (this is especially important when speaking about left and right). If speaking about some events that happened some other time than the present, it is sometimes assumed that all tenses are relative to that event which is being spoken about. In order to clarify that all tenses are relative to the speaker's current position, the word nau can be used at any time. Another word, ki, marks a tense which is then considered the new standard. Don't worry, there is no need to memorize these words right now. They will be taught much later.

Of course, it is also possible to specify the sumti of the sumtcita explicitly. This makes it possible to specify a temporal (or spacial) relation between two events. Here are a few examples:

Sentence Possible translation
mi dunda lo mlatu ba lo nu vecnu lo plise {kei} {ku} I donated (or am donating or will donate) the cat after selling the apple.
mi vecnu lo skami ca lo nu tavla do {kei} {ku} I sold (or am selling or will sell) the computer while talking to you.

Note that, in the first example, it is not clear whether the cat has been already donated, or even whether the apple has already been sold. We are just establishing a temporal relationship between "donating the cat" and "selling the apple", without specifying where they are positioned relative to now. The same applies principle to the second example as well.

Practice

As usual, before proceeding to the next lesson, get some practice with interactive exercises – look for the "Practice" button nearby!

Beware that exercises loop indefinitely, so feel free to stop once you feel you've had enough. And be sure to revisit exercises on different days, to benefit from the spacing effect.

Lesson plan

  • Lesson
    • Tenses
      • pu, ca, ba
  • New exercises
    • Choose "pu" vs "ca" vs "ba" (OK)
    • Translate specifying temporal tenses (OK)
    • Have some translations like "dunda ca lo nu tavla" (TODO)

Brivla

dunda x1 [donor] gives/donates gift/present x2 to recipient/beneficiary x3 [without payment/exchange]

pelxu x1 is yellow/golden [color adjective]

zdani x1 is a nest/house/lair/den/[home] of/for x2

tavla x1 talks/speaks to x2 about subject x3 in language x4

pendo x1 is/acts as a friend of/to x2 (experiencer); x2 befriends x1

prenu x1 is a person/people (noun) [not necessarily human]; x1 displays personality/a persona

mlatu x1 is a cat/[puss/pussy/kitten] [feline animal] of species/breed x2; (adjective:) x1 is feline

ctuca x1 teaches audience x2 ideas/methods/lore x3 (du'u) about subject(s) x4 by method x5 (event)

nelci x1 is fond of/likes/has a taste for x2 (object/state)

gerku x1 is a dog/canine/[bitch] of species/breed x2

melbi x1 is beautiful/pleasant to x2 in aspect x3 (ka) by aesthetic standard x4

sutra x1 is fast/swift/quick/hastes/rapid at doing/being/bringing about x2 (event/state)

lojbo x1 reflects [Loglandic]/Lojbanic language/culture/nationality/community in aspect x2

ciska x1 inscribes/writes x2 on display/storage medium x3 with writing implement x4; x1 is a scribe

djuno x1 knows fact(s) x2 (du'u) about subject x3 by epistemology x4

nupre x1 (agent) promises/commits/assures/threatens x2 (event/state) to x3 [beneficiary/victim]

cusku x1 (agent) expresses/says x2 (sedu'u/text/lu'e concept) for audience x3 via expressive medium x4

gleki x1 is happy/gay/merry/glad/gleeful about x2 (event/state)

citka x1 eats/ingests/consumes (transitive verb) x2

plise x1 is an apple [fruit] of species/strain x2

vecnu x1 [seller] sells/vends x2 [goods/service/commodity] to buyer x3 for amount/cost/expense x4

skami x1 is a computer for purpose x2

pilno x1 uses/employs x2 [tool, apparatus, machine, agent, acting entity, material] for purpose x3

cmene x1 (quoted word(s)) is a/the name/title/tag of x2 to/used-by namer/name-user x3 (person)

bangu x1 is a/the language/dialect used by x2 to express/communicate x3 (si'o/du'u, not quote)

fanva x1 translates text/utterance x2 to language x3 from language x4 with translation result x5

mukti x1 (action/event/state) motivates/is a motive/incentive for action/event x2, per volition of x3

gasnu x1 [person/agent] is an agentive cause of event x2; x1 does/brings about x2

Cmavo

mi pro-sumti: me/we the speaker(s)/author(s); identified by self-vocative

do pro-sumti: you listener(s); identified by vocative

ti pro-sumti: this here; immediate demonstrative it; indicated thing/place near speaker

ta pro-sumti: that there; nearby demonstrative it; indicated thing/place near listener

zo'e pro-sumti: an elliptical/unspecified value; has some value which makes bridi true

lo veridical descriptor: the one(s) that really is(are) ...

ku elidable terminator: end description, modal, or negator sumti; often elidable

fa sumti place tag: tag 1st sumti place

fe sumti place tag: tag 2nd sumti place

fi sumti place tag: tag 3rd sumti place

fo sumti place tag: tag 4th sumti place

fu sumti place tag: tag 5th sumti place

se 2nd conversion; switch 1st/2nd places

te 3rd conversion; switch 1st/3rd places

ve 4th conversion; switch 1st/4th places

xe 5th conversion; switch 1st/5th places

xu discursive: true-false question

ma pro-sumti: sumti question (what/who/how/why/etc.); appropriately fill in sumti blank

mo pro-bridi: bridi/selbri/brivla question

na bridi contradictory negator; scope is an entire bridi; logically negates in some cmavo compounds

go'i pro-bridi: preceding bridi; in answer to a yes/no question, repeats the claim, meaning yes

su'u abstractor: generalized abstractor (how); x1 is [bridi] as a non-specific abstraction of type x2

nu abstractor: generalized event abstractor; x1 is state/process/achievement/activity of [bridi]

du'u abstractor: predication/bridi abstractor; x1 is predication [bridi] expressed in sentence x2

sedu'u compound abstractor: sentence/equation abstract; x1 is text expressing [bridi] which is x2

kei elidable terminator: end abstraction bridi (often elidable)

vau elidable: end of sumti in simple bridi; in compound bridi, separates common trailing sumti

cu elidable marker: separates selbri from preceding sumti, allows preceding terminator elision

poi restrictive relative clause; attaches subordinate bridi with identifying information to a sumti

noi non-restrictive relative clause; attaches subordinate bridi with incidental information

ke'a pro-sumti: relativized sumti (object of relative clause)

ku'o elidable terminator: end NOI relative clause; always elidable, but preferred in complex clauses

be sumti link to attach sumti (default x2) to a selbri; used in descriptions

bei separates multiple linked sumti within a selbri; used in descriptions

be'o elidable terminator: end linked sumti in specified description

pi'o pilno modal, 1st place used by ...

mu'i mukti modal, 1st place because of motive ...

gau gasnu modal, 1st place agent/actor case tag with active agent ...

pu time tense relation/direction: did [selbri]; before/prior to [sumti]; default past tense

ca time tense relation/direction: is [selbri]; during/simultaneous with [sumti]; present tense

ba time tense relation/direction: will [selbri]; after [sumti]; default future tense

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