Like many Lojban grammatical constructions, sentence modal connection has both forethought and afterthought forms. (See Chapter 14 for a more detailed discussion of Lojban connectives.) Section 7 exemplifies only afterthought modal connection, illustrated here by:
8.1) mi jgari lei djacu .iri'abo mi jgari le kabri
I grasp the-mass-of water with-physical-cause I grasp the cup.
Causing the mass of water to be grasped by me, I grasped the cup.
I grasp the water because I grasp the cup.
An afterthought connection is one that is signaled only by a cmavo (or a compound cmavo, in this case) between the two constructs being connected. Forethought connection uses a signal both before the first construct and between the two: the use of “both” and “and” in the first half of this sentence represents a forethought connection (though not a modal one).
To make forethought modal sentence connections in Lojban, place the modal plus “gi” before the first bridi, and “gi” between the two. No “.i” is used within the construct. The forethought equivalent of Example 8.1 is:
8.2) ri'agi mi jgari le kabri gi mi jgari lei djacu
With-physical-cause I grasp the cup, I grasp the-mass-of water.
Because I grasp the cup, I grasp the water.
Note that the cause, the x1 of “rinka” is now placed first. To keep the two bridi in the original order of Example 8.1, we could say:
8.3) seri'agi mi jgari lei djacu gi mi jgari le kabri
With-physical-effect I grasp the-mass-of water, I grasp the cup.
In English, the sentence “*Therefore I grasp the water, I grasp the cup” is ungrammatical, because “therefore” is not grammatically equivalent to “because”. In Lojban, “seri'agi” can be used just like “ri'agi”.
When the two bridi joined by a modal connection have one or more elements (selbri or sumti or both) in common, there are various condensed forms that can be used in place of full modal sentence connection with both bridi completely stated.
When the bridi are the same except for a single sumti, as in Examples 8.1 through 8.3, then a sumti modal connection may be employed:
8.4) mi jgari ri'agi le kabri gi lei djacu
I grasp because the cup, the-mass-of water.
Example 8.4 means exactly the same as Examples 8.1 through 8.3, but there is no idiomatic English translation that will distinguish it from them.
If the two connected bridi are different in more than one sumti, then a termset may be employed. Termsets are explained more fully in Chapter 14, but are essentially a mechanism for creating connections between multiple sumti simultaneously.
8.5) mi dunda le cukta la djan. .imu'ibo la djan. dunda lei jdini mi
I gave the book to John. Motivated-by John gave the-mass-of money to-me.
I gave the book to John, because John gave money to me.
means the same as:
8.6) nu'i mu'igi mi le cukta la djan. gi la djan. lei jdini mi nu'u dunda
[start] because I, the book, John; John, the-mass-of money, me [end] gives.
Here there are three sumti in each half of the termset, because the two bridi share only their selbri.
There is no modal connection between selbri as such: bridi which differ only in the selbri can be modally connected using bridi-tail modal connection. The bridi-tail construct is more fully explained in Chapter 14, but essentially it consists of a selbri with optional sumti following it. Example 7.3 is suitable for bridi-tail connection, and could be shortened to:
8.7) mi mu'igi viska le cukta gi lebna le cukta
I, because saw the book, took the book.
Again, no straightforward English translation exists. It is even possible to shorten Example 8.7 further to:
8.8) mi mu'igi viska gi lebna vau le cukta
I because saw, therefore took, the book.
where “le cukta” is set off by the non-elidable “vau” and is made to belong to both bridi-tails — see Chapter 14 for more explanations.
Since this is a chapter on rearranging sumti, it is worth pointing out that Example 8.8 can be further rearranged to:
8.9) mi le cukta mu'igi viska gi lebna
I, the book, because saw, therefore took.
which doesn’t require the extra “vau”; all sumti before a conjunction of bridi-tails are shared.
Finally, mathematical operands can be modally connected.
8.10) li ny. du li vo
.ini'ibo li ny. du li re su'i re
the number n = the-number 4.
Entailed-by the-number n = the-number 2 + 2.
n = 4 because n = 2 + 2.
can be reduced to:
8.11) li ny. du li ni'igi vei re su'i re [ve'o] gi vo
the-number n = the-number because ( 2 + 2 ) therefore 4.
n is 2 + 2, and is thus 4.
The cmavo “vei” and “ve'o” represent mathematical parentheses, and are required so that “ni'igi” affects more than just the immediately following operand, namely the first “re”. (The right parenthesis, “ve'o”, is an elidable terminator.) As usual, no English translation does Example 8.11 justice.
Note: Due to restrictions on the Lojban parsing algorithm, it is not possible to form modal connectives using the “fi'o”-plus-selbri form of modal. Only the predefined modals of selma'o BAI can be compounded as shown in Sections 7 and 8.