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Lesson 5: Times, days, dates

One way to ask the question "What is the time?" is ma tcika. We know that ma is the sumti question word, so tcika must be a selbri meaning "is the time", with the ti meaning "this event", or, in other words "now". The place structure of tcika is

x1 (hours, minutes, seconds) is the time of state/event x2 on day/date x3, at location x4, by calendar x5

A full answer would obviously be very long-winded, but remembering the Lojban convention that you miss out all the places after the last one you really need, a typical exchange would be:
  1. ma tcika ti
  2. li vo
  1. "What's the time?"
  2. "Four"
Note the li, since we are talking about a number here. li vo is short for li vo cu tcika ti—"four is the time of this (event)".

If we want to be a bit more precise, we need to use pi'e. This is like pi, but doesn't need to keep the same value. In normal counting, pi is a decimal point, in hexadecimal it's a hexadecimal point and so on, but it never changes its value. pi'e doesn't have that restriction, so we can use it to separate hours from minutes. So an alternative answer to the question could be

li vo pi'e mu
"Five past four."
or if you want to be particularly precise,
li vo pi'e mu pi'e pabi
"Five minutes and eighteen seconds past four."
Let's imagine, though, that the time is not five past four, but five to four. We can still say li ci pi'e mumu (4:55) but we can also say li vo pi'e ni'u mu. ni'u is the Lojban minus sign (for negative numbers, not for subtraction)—what we are saying is "4:-5".

For "half past four" you can also use pi and say li vo pimu—4.5. I don't particularly like this method, but it is perfectly good Lojban. If we are using numbers for times, it is normal to use the 24-hour system, so 6 p.m. is li pabi (18:00).

Another possibility, is to use cmene for hours, so "four o'clock" is la vocac., "five o'clock" is la mucac. and so on. For 11 and 12 we need extra numbers. Fortunately Lojban has these and more; the number system actually goes up to 16 (hexadecimal), so we have the extra numbers

dau
10
fei
11
gai
12
jau
13
rei
14
vai
15
Obviously for anything other than talking about computer programming, the numbers 13-15 are useless, but we can use 10-12 for hours. "Ten o'clock" is la daucac. "Eleven o'clock" is la feicac.and "twelve o'clock" is la gaicac.. For "morning" and "evening" we can then add lir. and lec., meaning "early" and "late". So la mucaclir. is five in the morning.

Exercise 1

What are the following times in Lojban?
  1. Nine o'clock
  2. Eleven o'clock in the morning.
  3. Two in the afternoon.
  4. Midnight.
  5. 9:25
  6. 12:15
  7. 14:30
  8. 17:50
If we want to give the time of an event, rather than just tell the time, we need to fill in some more places. The second place of tcika is "state/event", so we need some way to show that the sumti in this position is a state or an event, and not a thing.

la daucac. tcika le mi klama

does not mean "Ten o'clock is the time that I go" (or come!), but "Ten o'clock is the time of my goer," which is meaningless. We get round this problem with the word nu, which means—you guessed—"state/event". This is called an "abstraction descriptor" (or "abstractor" for short), other common descriptors being ka (quality or property), ni (amount) and so on (for a complete list, see The Complete Lojban Language, p. 269). What nu does here is allow us to put a whole bridi into a sumti place. It's usually written together with the article (le or lo) but is actually a separate word. So what we want is

la daucac. tcika lenu mi klama

(note that there is no cu here, since la daucac. is a cmene)

If "Ten o'clock is the time that I go" sounds backwards, there are two ways you can switch it round. One is using se, which swaps the first and second places of the bridi.

le nu mi klama cu se tcika la daucac.

means exactly the same thing. se is co-incidentally is pretty much the same as Spanish "se", but is actually part of a series along with te, ve and xe, which convert the first and third, first and fourth, and first and fifth places. These aren't used so much in sentences as se, but are often used in making lujvo (compound words), as we'll see later in the course.

Still too long and clumsy? Get ready for more Lojban tricks. It would be really nice if klama had a place for the time of going/coming, but it doesn't (after all, you wouldn't really want a six-place selbri!). To get round this problem of missing places, Lojban has a series of "tags" of the class BAI. The one we want here is ti'u, meaning "with time". So we can now say

mi klama ti'u la daucac.

So why, you may ask, didn't I just say that in the first place? I could have done, but then you wouldn't have found out about nu and se! There is more to this lesson than meets the eye.

Days and Months

The days of the week are also numbers, this time adding djed., from the gismu, djedi, meaning "day". There is at present some disagreement about which day should be day one, though. The original convention was to follow the Judeo-Christian convention of taking Sunday as the first day, giving
Sunday
la padjed.
Monday
la redjed.
Tuesday
la cidjed.
... and so on. However, in a meeting in 1992 it was agreed that Monday be day 1, and Sunday be either 7 (la zedjed.) or zero (la nodjed.) according to taste. Eventually, though, people will use whichever system they prefer until one becomes universally accepted. This may sound chaotic, but I have gone into this point as a good example of how in Lojban a large part of the language is "left to usage"—meaning that ultimately the language depends on the way people choose to use it in practice. People are also free to work out alternative conventions for cultures which do not use a seven-day week, possibly adding to the name to make it clear; e.g. la padjedjung. could be the first day of the Chinese ten-day week.

Months also use numbered cmene, adding mast., so January is la pamast. and so on. Again, since there are twelve months, we use the extra numbers, so October is la daumast..

Exercise 2

What are these days and months in Lojban?
  1. Saturday
  2. Thursday
  3. March
  4. August
  5. November
  6. December
Just in case you're interested, the words for seasons are:
vensa
Spring
crisa
Summer
critu
Autumn
dunra
Winter
for full definitions of these words, see the gismu list). If the seasons where you live don't match this pattern, then you can easily create new words. For example, the rainy season or monsoon could be carvycitsi (from carvi, rain, and citsi, season) or simply la carv. . Here are some I made up for fun to give a better idea of the weather in the UK:
la lekcarv.
"the cold rain"—Spring
la mliglacarv.
"the warm (mildly-hot) rain"—Summer
la bifcarv.
"the windy rain"—Autumn
la duncarv.
"the freezing rain"—Winter
Joking aside, this shows two features of word-building in Lojban: making cmene by losing the final vowel (which we saw in Lesson 1) and creating lujvo, or compound words. You actually need a pretty good knowledge of Lojban to make up lujvo on the spot, but we'll learn how to make simple lujvo later on in this course.

Dates

The gismu for dates is detri:

x1 is the date (day, week, month, year) of state/event x2, at location x3, by calendar x4

Phew! Like tcika, though, most places of detri can be left out. The location is only important if we're talking about radically different timezones, or different planets, and the calendar is normally assumed to be the standard Western one—if you want to use, for example, the Arabic or Chinese calendars, you can put le xrabo or le jungo in the fourth place (as always, context is important—in a discussion of Islamic history we would probably assume that the Arabic calendar was being used).

The tricky bit is the number in x1. Normally we don't want to specify the day, week, month and year! To prevent confusion, the following conventions are used:

  1. If there is only one number, it is the day e.g. li pano is "the 10th".
  2. If there are two numbers, they are the day and month e.g. li pano pi'e pare is 10/12, or "the 10th of December".

If there are three numbers, they are day, month, year (not month, day, year, as in the American convention) e.g. li repa pi'e ze pi'e pasoxaso is 21/7/69 - the date of the first moon landing.

We can therefore say
li repa pi'e ze pi'e pasoxaso cu detri lenu lo remna cu pamoi klama le lunra
21/7/1969 is-the-date-of the-event a human first go (to) the moon
Here we have another case of abstraction with nu. Just like articles have the terminator ku (which is usually missed out), abstractors like nu have the terminator kei. kei is not necessary in this particular sentence, because the abstraction comes at the end, but it would be necessary if there were other places after x2—if, for example we wanted to emphasise that this was the date in Houston (but not in Tokyo) we would say
li repa pi'e ze pi'e pasoxaso cu detri lenu lo remna cu pamoi klama le lunra kei la xustyn.
21/7/1969 is-the-date-of the-event a human first go (to) the moon (according to the time at) Houston
The kei here is important, as it is necessary to stop the nu abstraction running into la xustyn., which would make the sentence say that a person went to the moon from Houston—true, but not what we want. By the way, if you're wondering why kei wasn't necessary in the tcika example, it was because the cu marked the next word as the main selbri.

Just as with tcika, we often want to put the event first—after all in most languages we would normally say "My birthday is on the fifteenth of August" rather than "The fifteenth of August is the date of my birthday." We can manage this change by using place tags, e.g.

fe lenu mi jbena [kei] cu detri fa li pamupi'ebi
the-event I am-born is-dated 15/8
but it is easier to use se like this:
lenu mi jbena cu se detri li pamupi'ebi
the-event I am-born is-dated 15/8
And, as you probably guessed, there is a BAI tag for "dated": de'i (notice how BAI tags tend to be similar to the selbri they suggest). So the other way I can tell you my birthday is mi jbena de'i li pamupi'ebi

Question: If only one number is used with detri, it is the day. So how do we say what year an event happened without giving the day and month as well?

The gismu, nanca cannot be used instead of detri, since it has the place-structure "x1 is x2 years in duration, by standard x3," i.e. it gives the length of an event in years, not the year when an event happened. One way out is to use a cmene for the year, so the year I am writing this would be la pasososonanc.

Exercise 3—history quiz

Give the dates to answer these questions, using cmene for the years.
  1. lenu la kolombus. facki lo cnino gugde cu se detri ma
  2. la mexmet. dable'a la konstantinopolis. de'i ma
  3. lenu fraso jecyga'ibai cu se detri ma
  4. la marks. .e la .engels. ciska le guntrusi'o selpeicku ku de'i ma
  5. la muxamed. klama la medinas. de'i ma
Vocabulary:
facki
find, discover
cnino
new
gugde
country
dable'a
conquer, sieze ("war-take")
fraso
French
jecyga'ibai
revolution ("government-change-force")
guntrusi'o
Communist ("work-govern-idea")
selpeicku
manifesto ("thought-book")

Summary

Apart from times and dates, this lesson has covered some important points of Lojban grammar.

Answers to Exercises

Exercise 1

  1. la socac.
  2. la feicaclir.
  3. la recaclec.
  4. la revocac. or la gaicaclir. (if you follow the convention that midnight is 12 a.m.)
  5. li sopi'eremu
  6. li parepi'epamu
  7. li pavopi'ecino or li pavopimu
  8. li pazepi'emuno or li pabani'upano

Exercise 2

  1. la zedjed.
  2. la mudjed.
  3. la cimast.
  4. la bimast.
  5. la feimast.
  6. la gaimast.

Exercise 3

  1. la pavosorenanc.
  2. la pavomucinanc.
  3. la pazebisonanc.
  4. la pabivobinanc.
  5. la xarerenanc. (or la pananc., if you're using the Muslim calendar)

Last modified: Mon Jun 27 23:12:59 PDT 2005

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