So far we've been referring to everybody by name, which can get very repetitive if you want to tell a story, or even string two sentences together (as you will have seen in the last few exercises.) Consider the following:
la suzyn. klama le barja .i la suzyn ze'a pinxe loi vanju .i la suzyn. zgana lo nanmu .i le nanmu cu melbi .i le nanmu cu zgana la suzyn.
Susan goes to the bar. Susan drinks some wine for a while. Susan notices [sees, observes] a man. The man is beautiful. The man notices Susan.
Note: Notice the use of melbi — in English we usually describe men as 'handsome' rather than 'beautiful', but this rather sexist distinction doesn't apply in Lojban. However, if you really wanted a Lojban word for 'handsome' (beautiful–kind-of–man) you could say melnau (melbi + nanmu).
It is pretty tedious to have to keep repeating Susan and man. English gets round this problem by using pronouns, like she or he. This works OK in this case, because we have one female and one male in the story so far, but it can get confusing when more characters enter the scene. (It's even more confusing with languages that only have one word for he, she and it, like Turkish or spoken Chinese.) Lojban, for its part, has pro-sumti, which are like pronouns — sort of.
In fact, we've already met some pro-sumti: mi and do, and the ti/ta/tu group; but we still don't have he/she/it, which are a bit more complicated. One way of dealing with this is a group of cmavo which refer back to something we've just said. In fact we have met one of these in a different context: go'i. Just as go'i on its own repeats the previous bridi, le go'i repeats the first sumti of the previous bridi. (In this, it is behaving no differently to any other selbri with an article in front of it: le + selbri refers to the x1 of that selbri.) So we can rewrite the first three sentences as
la suzyn. klama le barja .i le go'i ze'a pinxe loi vanju .i le go'i cu zgana lo nanmu
The system breaks down here, though, since nanmu is not in the first, but the second place of the previous bridi. English doesn't bother with precision here — he just means 'some male person mentioned earlier.' This works in the example here, because there is only one man in the story, but what about
Did Bill hit Rick, or did Rick hit Bill? We don't know. Lojban does have other tricks up its sleeve, and as you might just have already guessed, le se go'i will do the trick. But counting sumti from the preceding bridi isn't really a general solution.
Bill saw Rick. He hit him.
Coming back to the man Susan saw, we can refer to him as ri, which means 'the most recent sumti.' So we can say
ri is one of a series, ri/ra/ru, meaning 'the most recent/fairly recent/distant sumti'; but as far as I've noticed, ra and ru aren't very popular in Lojbanistan at the moment. (Put it down to ideological reasons: they are deliberately vague, like their natural language counterparts, so they are regarded as somehow 'un-Lojbanic'.) ri, on the other hand, is used a lot, since it's very common for the last thing in one sentence to be the subject of the next sentence.
.i le go'i cu zgana lo nanmu .i ri melbi
Tip: sumti are counted from their beginnings. So in a sentence likeri refers to lo nanmu and not lenu lo nanmu cu dotco: the start of lo nanmu is closer to ri than the start of lenu lo nanmu cu dotco.
lenu lo nanmu cu dotco kei cu se djuno ri
Tip: ri cannot refer to a sumti if it is already smack in the middle of that sumti. For example, inri obviously refers to la suzyn., and not to le vanju.
la suzyn. pinxe le ri vanju
Another pro-sumti is da, which means 'someone/something.' You may remember zo'e, which means also means 'someone/something,' but with zo'e the something is unimportant — it's just a way of filling a sumti place. da, on the other hand, is important: it introduces something or someone we are directly talking about.
Note for logicians: da is the 'existential x', as in "There exists some x such that x is ..."
Coming back to our story, we could start by saying da klama le barja — "Someone came to the bar." Unlike the other pro-sumti we've been looking at, da does not point back to a sumti we've necessarily already seen. It does, however, point back to the same thing as any other da in any sentences conjoined with logical connectives, or more informally anywhere in the same paragraph. (No, we haven't done Lojban logical connectives or paragraphs yet... Just keep this in mind for future reference.) So if I say da nanmu .i da klama le barja, you can typically assume I'm referring to the same man in both sentences.
Because they are all tied up with predicate logic, da and its companions de and di are used a lot for talking about language — you see them frequently on the Lojban e-mail list, for example. By the way, there are no do and du in this series, because these already have other meanings: 'you' and 'is the same thing as.'
The two highlighted sumti in each of the following Lojban sentences refer to the same thing or person. For each, check whether the pro-sumti you have learned — lego'i, ri, ra — can replace the second sumti.