If one element of a tanru can be another tanru, why not both elements?
4.1) do mutce bo barda gerku bo kavbu
You are-a-(very type-of large) (dog type-of capturer).
You are a very large dog-catcher.
In Example 4.1, the selbri is a tanru with seltau “mutce bo barda” and tertau “gerku bo kavbu”. It is worth emphasizing once again that this tanru has the same fundamental ambiguity as all other Lojban tanru: the sense in which the “dog type-of capturer” is said to be “very type-of large” is not precisely specified. Presumably it is his body which is large, but theoretically it could be one of his other properties.
We will now justify the title of this chapter by exploring the ramifications of the phrase “pretty little girls’ school”, an expansion of the tanru used in Section 3 to four brivla. (Although this example has been used in the Loglan Project almost since the beginning — it first appeared in Quine’s book Word and Object (1960) — it is actually a mediocre example because of the ambiguity of English “pretty”; it can mean “beautiful”, the sense intended here, or it can mean “very”. Lojban “melbi” is not subject to this ambiguity: it means only “beautiful”.)
Here are four ways to group this phrase:
4.2) ta melbi cmalu nixli ckule
That is-a-((pretty type-of little) type-of girl) type-of school.
That is a school for girls who are beautifully small.
4.3) ta melbi cmalu nixli bo ckule
That is-a-(pretty type-of little) (girl type-of school).
That is a girls’ school which is beautifully small.
4.4) ta melbi cmalu bo nixli ckule
That is-a-(pretty type-of (little type-of girl)) type-of school.
That is a school for small girls who are beautiful.
4.5) ta melbi cmalu bo nixli bo ckule
That is-a-pretty type-of (little type-of (girl type-of school)).
That is a small school for girls which is beautiful.
Example 4.5 uses a construction which has not been seen before: “cmalu bo nixli bo ckule”, with two consecutive uses of “bo” between brivla. The rule for multiple “bo” constructions is the opposite of the rule when no “bo” is present at all: the last two are grouped together. Not surprisingly, this is called the “right-grouping rule”, and it is associated with every use of “bo” in the language. Therefore,
4.6) ta cmalu bo nixli bo ckule
That is-a-little type-of (girl type-of school).
means the same as Example 3.4, not Example 3.5. This rule may seem peculiar at first, but one of its consequences is that “bo” is never necessary between the first two elements of any of the complex tanru presented so far: all of Examples 4.2 through 4.5 could have “bo” inserted between “melbi” and “cmalu” with no change in meaning.