Sometimes it is necessary or useful to attach more than one relative clause to a sumti. This is made possible in Lojban by the cmavo zi'e (of selma'o ZIhE), which is used to join one or more relative clauses together into a single unit, thus making them apply to the same sumti. For example:

The most usual translation of zi'e in English is “and”, but zi'e is not really a logical connective: unlike most of the true logical connectives (which are explained in Chapter 14), it cannot be converted into a logical connection between sentences.

It is perfectly correct to use zi'e to connect relative clauses of different kinds:

In Example 8.39, the restrictive clause poi blabi specifies which dog is referred to, but the incidental clause noi le mi pendo cu ponse is mere incidental information: the listener is supposed to already have identified the dog from the poi blabi. Of course, the meaning (though not necessarily the emphasis) is the same if the incidental clause appears first.

It is also possible to connect relative phrases with zi'e, or a relative phrase with a relative clause:

Note that if the colloquial translation of Example 8.40 were “My bottle, which is blue, is broken”, then noi rather than poi would have been correct in the Lojban version, since that version of the English implies that you do not need to know the bottle is blue. As written, Example 8.40 suggests that I probably have more than one bottle, and the one in question needs to be picked out as the blue one.

Example 8.41 illustrates that more than two relative phrases or clauses can be connected with zi'e. It almost defies colloquial translation because of the very un-English contrast between pe mi, implying that the chair is temporarily connected with me, and po do, implying that the chair has a more permanent association with you. (Perhaps I am a guest in your house, in which case the chair would naturally be your property.)

Here is another example, mixing a relative phrase and two relative clauses, a restrictive one and a non-restrictive one: