The following cmavo is discussed in this section:

Normally, relative clauses attach only to simple sumti or parts of sumti: pro-sumti, names and descriptions, pure numbers, and quotations. An example of a relative clause attached to a pure number is:

And here is an incidental relative clause attached to a quotation:

which may serve to identify the author of the quotation or some other relevant, but subsidiary, fact about it. All such relative clauses appear only after the simple sumti, never before it.

In addition, sumti with attached sumti qualifiers of selma'o LAhE or NAhE+BO (which are explained in detail in Section 6.10) can have a relative clause appearing after the qualifier and before the qualified sumti, as in:

Example 8.68 is a bit complex, and may need some picking apart. The quotation lu le xunre cmaxirma li'u means the string of words “The Red Pony”. If the la'e at the beginning of the sentence were omitted, Example 8.68 would claim that a certain string of words is in a room distant from the speaker. But obviously a string of words can't be in a room! The effect of the la'e is to modify the sumti so that it refers not to the words themselves, but to the referent of those words, a novel by John Steinbeck (presumably in Lojban translation). The particular copy of “The Red Pony” is identified by the restrictive relative clause. Example 8.68 means exactly the same as:

and the two sentences can be considered stylistic variants. Note the required lu'u terminator, which prevents the relative clause from attaching to the quotation itself: we do not wish to refer to an old quotation!

Sometimes, however, it is important to make a relative clause apply to the whole of a more complex sumti, one which involves logical or non-logical connection (explained in Chapter 14). For example,

The incidental claim in Example 8.70 is not that Frank and George are men, but only that George is a man, because the incidental relative clause attaches only to la djordj, the immediately preceding simple sumti.

To make a relative clause attach to both parts of the logically connected sumti in Example 8.70, a new cmavo is needed, vu'o (of selma'o VUhO). It is placed between the sumti and the relative clause, and extends the sphere of influence of that relative clause to the entire preceding sumti, including however many logical or non-logical connectives there may be.

The presence of vu'o here means that the relative clause noi nanmu extends to the entire logically connected sumti la .frank. .e la .djordj.; in other words, both Frank and George are claimed to be men, as the colloquial translation shows.

English is able to resolve the distinction correctly in the case of Example 8.70 and Example 8.71 by making use of number: “who is” rather than “who are”. Lojban doesn't distinguish between singular and plural verbs: nanmu can mean “is a man” or “are men”, so another means is required. Furthermore, Lojban's mechanism works correctly in general: if nanmu (meaning “is-a-man”) were replaced with pu bajra (“ran”), English would have to make the distinction some other way:

In spoken English, tone of voice would serve; in written English, one or both sentences would need rewriting.