Which Way Which?

Now that I've finally reached the chapters in Judd that deal with more interesting grammar, I am much happier.

A monolingual English-speaker (aka "American") might not realize this, but the structure of the relative clause in English (who/whom/whose/which/what) is remarkably free. English allows nearly component of a clause to become the pivot on which the subordinate clause hinges. Other languages, such as Biblical Hebrew, have only one form; thus the English sentence "I saw the fish which the man caught" becomes "Saw I the fish which the man caught it." Biblical Hebrew's construction is fairly simply compared to the hoops some languages jump through: languages that have cases but insist that the relative particle be in one case (nominative or ergative, depending on the overall linguistic structure) can twist themselves into knots if the pivotal noun is not the actual subject of both sentences.

Hawaiian uses a relative particle, but is not a fan of relative clauses. In many domains, places where one could use a relative particle prefer a particle associated with the main clause. There are, however, three places where a relative particle is mandatory. The first case:
Na mea ana i ike ai. The things which he saw.
A rougher, but perhaps more illuminating, translation would be "The things of him (inalienable), past see which." The subject of the subordinate clause ("he") cannot stand its normal main clause position directly following the verb within the subordinate clause, since the relative particle ai is occupying that slot; nor can it take its normal main clause position in the main clause, since the noun phrase na mea occupies that position. A relative particle, however, is useless without a noun or pronoun to relate to, so the subject of the subordinate clause ("he") transforms and becomes an a-class genitive modifying the subject of the main clause. A-class genitives and possessives seem to be popular choices for grammatical transformations in Hawaiian.
The second case:
Eia ka mea i make ai na kanaka. Here is the cause from which the men died.
The rough translation would be "Here the cause (mea is a remarkably flexible word, meaning person, thing, or cause) past die which the men." Ai is used here because it replaces means, cause, or instrument. I am not entirely sure why ai precedes na kanaka - perhaps it is part of the verb complex, or perhaps the relative particle needs to be as close to its antecedent as possible.
The third case:
I ka la a makou i hiki mai ai. On the day when we came.
A rough translation would be "On the day when we (plural, exclusive) past come away-from-speaker which."The prepositional phrase i ka la has been fronted and its position occupied by ai. The conflation of time and place, when and where, is so common in language that I wonder if it is not a fundamentally human way of understanding the world. It is worth noting that the subject of the subordinate clause, makou, here precedes its verb, i hiki, even though the default order of the original sentence would be I hiki mai makou i ka la. A different word order in subordinate clauses from main clauses is quite common in the world's languages, but I am not certain why *I ka la a i hiki mai ai makou would be a challenge to a native Hawaiian speaker. It might mean something slightly different, or it might just be one of those things about a language that a tyro must learn.

If these three examples are typical (and I cannot imagine why one would use atypical examples in such a small sample in a teaching grammar), I would not be surprised if ai batted for the verbal team rather that the nominal one, insofar as any Hawaiian word has a firm verbal/nominal distinction; the possibility of replacing ai with the gerund-making particle ana supports this idea. If this were the case, then the three sentences have the following rough translations: "His things seen-which", "Here the cause died-which the men," and "On the day when we (but not you) came-away-from-speaker-which." Additionally, if ai were verbal in this way, it also seems to trigger a loss of valency, changing the verb from transitive to intransitive.