When using tenses, the CLL describes a way to use termsets to specify an exact distance. For example, mi klama be'a nu'i zo'e la'u lo minli be li mu gives an exact distance from the speaker, indicating the walking occurred five miles north. This has several usability issues. First, it requires the use of two places, which means you must specify both the anchor point and the measure. Second, it requires the use of the klani modal, which is both not particularly well-specified and adds additional verbosity in expressing exact distances.
In zantufa and some other dialects, all the tenses are treated in the same way as BAI. BAI may be used with SE in order to gain access to additional meanings with a connected idea.
These two behaviors may be combined to great effect. When speaking selba, all BAI and tenses are permitted to include a termset, which will fill places sequentially, and may be tagged with FA to jump to specific places within the structure. Additionally, tenses prefixed with SE will be converted to have places beyond the first be used without requiring a termset. This extension requires that a place structure be defined systematically for tenses. These structures are outlined below.
Tenses which specify a direction all follow this pattern:
x1 is the tagged point for an imaginary journey, traveling in [direction] for a distance of x2
This allows an exact distance to be specified. For example, mi klama sebe'a lo minli be li mu has the same meaning as the first example sentence in this article.
Tenses which specify a subjective distance do not provide a way to specify an exact distance, for that, use BA and similar. These tenses follow this pattern:
x1 is the tagged point for an imaginary journey, traveling [subjective distance], with standard of subjective size x2
This allows context for perceived distance to be provided. mi klama sevu tu'a lonu cadzu indicates that the going was done very far from the speaker's location, in the context of what is far for walking.
Tenses which specify an interval or area follow this pattern:
x1 is the tagged point for an imaginary journey, spreading out in [subjective sized area] with a volume/area/size x2, with standard of subjective size x3
This allows for both perceived size and actual value to be provided. mi klama seve'a lo pitki'otre be li re indicates the going was all done within a two square kilometer area of the speaker.
Tenses which specify a relation between the event and another point follow this pattern.
x1 is the tagged point for an imaginary journey, going to a point on the event specified by [relative location], separated from [anchor] by distance x2
This allows expressing ideas previously quite difficult, such as "she arrived 5 minutes before guests were supposed to" can now be expressed as darca sexa'o lo mentu be li mu. Without this construction such a sentence would be long and unwieldy, as e.g. darca ca lo se temci be lo mentu be li mu be'o bei lo zgadi.
Tenses which specify that two points coincide directly, but with no relation to a point separated from the two, have no unified place structure under selba at this time.
The ZAhO selma'o has not classically been split into multiple sub-selma'o. Along with the proposals about place structure, selba proposes the following split for official ZAhO:
- pu'o before the beginning
- ba'o after the end
- xa'o performing before it should start
- za'o continuing after it should end
- co'a beginning after it should
- co'u stopping before it should
- co'i the whole
- ca'o the duration
- xo'u the beginning
- mo'u the end
- de'a a pause
- di'a a resumption
Comparison with BPFK
selba is not the only proposed solution to the clunkiness of specifying exact distances in tense. The BPFK Section on Distance specifies that distance sumtcita like ZI and ZEhA, when tagging a sumti, that sumti specifies the distance. While this initially seems easier, it has some issues with certain sentences which become much harder to express.
For example, the sentence "I'll go a while after I eat", the way in CLL lojban and in selba to say this is the following:
mi klama baza lonu mi citka
Under BPFK, the above sentence means "I will go after an amount of time equal to the length of me eating something", which doesn't place the outer bridi relative to a particular event of eating at all. If you wish to retain this meaning in BPFK lojban, you must write something like the following:
lonu mi klama cu mlimli balvi lonu mi citka
The difference of whether or not the first statement is claimed notwithstanding, this is significantly clumsier. Alternatively, if you intended for the meaning "I will go to the store after the length of time it takes me to eat", the way you would say this with CLL is clearly more verbose than the above sentence interpreted by BPFK:
mi klama baza zo'e ce'e la'u lo krafamtei be lonu mi citka
When expressing this with selba however, it lacks much of this verbosity, instead simply using se:
mi klama seba lonu mi citka
The only notable difference here is that it lacks the claim that the length of time is "of middling length" as the CLL version does, but this matches closer with the BPFK semantics where za lacks a specific subjective length.