Direct-inverse voice systems have been described most famously for Algonquian languages, but there are a few other cases in the world, as well. Not many, though. I would like to suggest that they are more common than people think, and linguists should start paying more attention to the grammatical properties of inverse systems.
An example of a direct-inverse voice system is Plains Cree. In Plains Cree, if there are two (or more) third-person arguments in the same clause, one is proximate (unmarked) and the other(s) obviative (marked with the suffix -ah). If the proximate NP is the subject, the direct voice is used (glossed ``3/Obv,'' meaning a proximate (3) acting on an obviative (Obv). If the proximate NP is instead the object, the inverse voice is used (glossed ``Obv/3''). The following examples, from Dahlstrom 1991 (pp64--66), illustrate the direct (1) and the inverse (2):
(1) aya:hciyiniw-ah nisto e:h=nipah-a:t awa na:pe:sis
Blackfoot-Obv three kill-3/Obv.Conj this boy
`this boy had killed three Blackfoot'
(2) ta:pwe: mac-a:yi:siyiniw e:sah nipah-ik o:hi ihkw-ah
truly bad-person kill-Obv/3 this.Obv louse-Obv
`truly the louse killed the evil man'
What characterizes the inverse is a reversal of syntactic prominence: the thematic external argument seems to be hierarchically subordinate to the thematic internal argument, regardless of surface word order. This reversal of prominence is reflected in binding, scope, and other facts; see Bruening 2009. It is important to note that the inverse is not a passive: the external argument has not been removed or demoted to an oblique. Plains Cree also has a passive (or ``indefinite subject'' form), which lacks a thematic external argument:
(3) ki-kosis nipah-a:w
`your son has been killed'
Let's now look at Mandarin Chinese. This language is usually described as basically SVO, as in the following example (from Li 2006):
(4) wo sha-le ta-le
I kill-Asp him-Asp
`I killed him.'
However, other word orders are possible, like OSV or even SOV; these are usually described as some sort of topicalization.
There are also two constructions that I would like to put side-by-side, the ba-construction and the bei-construction (5 is from Li 2006, but 6 comes from my own consultants):
(5) wo ba ta sha-le
I BA him kill-Asp
`I killed him.'
(6) ta bei wo sha-le
he BEI I kill-Asp
`He was killed by me.'
Suppose Mandarin Chinese did not have examples like (4), and all sentences were either like (5) or like (6). Linguists would then describe the voice system of Mandarin Chinese as a direct-inverse system: (5) is the direct voice, with the thematic external argument highest hierarchically, and (6) is the inverse voice, with the thematic external argument subordinate to an internal argument.
This is not how most linguists describe Mandarin; instead, (6) is referred to as a ``passive,'' while (5) is the mysterious ``ba-construction.'' However, (6) has nothing in common with Indo-European-type passives: the thematic external argument has not been demoted or removed, it retains its status as an argument (see Huang 1999). Now, the external argument can be removed, and be interpreted as an indefinite:
(7) ta bei sha-le
he BEI kill-Asp
`He was killed (by someone).'
However, as we saw above, direct-inverse languages like Plains Cree also have a passive, in addition to direct-inverse clauses. The presence of (7) therefore in no way undermines the idea that the bei-construction in (6) is an inverse.
I suggest that a more accurate terminology for Mandarin Chinese would be to call SVO sentences like (4) ``unmarked,'' and (5) and (6) ``direct'' and ``inverse,'' respectively. Linguists should then turn to the study of inverse sentences (and direct ones), both from a theoretical and from a typological standpoint. Constructions like the bei-construction in Mandarin Chinese are very common among Asian languages, and the potential to deepen our understanding of language by taking a new perspective is great.
Bruening, Benjamin (2009). Algonquian Languages Have A-Movement and A-Agreement. Linguistic Inquiry 40: 427--445.
Dahlstrom, Amy (1991). Plains Cree Morphosyntax. New York: Garland.
Huang, C.-T. James (1999). Chinese Passives in Comparative Perspective. Tsing Hua Journal of Chinese Studies 29: 423--509.
Li, Yen-Hui Audrey (2006). Chinese Ba. In Martin Everaert and Henk van Riemsdijk (eds.), The Blackwell Companion to Syntax volume 1, pp 374--468. Oxford: Blackwell.