The following notations will be used to discuss the various types of alignment:12
Note that while the labels S, A, O/P originally stood for subject, agent, object, and patient, respectively, the concepts of S, A, and O/P are distinct both from the grammatical relations and thematic relations. In other words, an A or S need not be an agent or subject, and an O need not be a patient.
Note, however, that these semantic macro-roles in Dixon's model differ from those in Klimov's model (1983), which uses five macro-roles (with both S and O divided into two categories).3
In a nominative–accusative system, S and A are grouped together, contrasting O. In an ergative–absolutive system, S and O are one group and contrast with A. The English language represents a typical nominative–accusative system (accusative for short). The name derived from the nominative and accusative cases. Basque is an ergative–absolutive system (or simply ergative). The name stemmed from the ergative and absolutive cases. S is said to align with either A (as in English) or O (as in Basque) when they take the same form.
Listed below are argument roles used by Bickel and Nichols for the description of alignment types.4 Their taxonomy is based on semantic roles and valency (the number of arguments controlled by a predicate).
The term locus refers to a location where the morphosyntactic marker reflecting the syntactic relations is situated. The markers may be located on the head of a phrase, a dependent, and both or none of them.56
The direct, tripartite, and transitive alignment types are all quite rare. The alignment types other than Austronesian alignment can be shown graphically like this:
In addition, in some languages, both nominative–accusative and ergative–absolutive systems may be used, split between different grammatical contexts, called split ergativity. The split may sometimes be linked to animacy, as in many Australian Aboriginal languages, or to aspect, as in Hindustani and Mayan languages. A few Australian languages, such as Diyari, are split among accusative, ergative, and tripartite alignment, depending on animacy.
A popular idea, introduced in Anderson (1976),10 is that some constructions universally favor accusative alignment while others are more flexible. In general, behavioral constructions (control, raising, relativization) are claimed to favor nominative–accusative alignment while coding constructions (especially case constructions) do not show any alignment preferences. This idea underlies early notions of ‘deep’ vs. ‘surface’ (or ‘syntactic’ vs. ‘morphological’) ergativity (e.g. Comrie 1978;11 Dixon 199412): many languages have surface ergativity only (ergative alignments only in their coding constructions, like case or agreement) but not in their behavioral constructions or at least not in all of them. Languages with deep ergativity (with ergative alignment in behavioral constructions) appear to be less common.
The arguments can be symbolized as follows:
The S/A/O terminology avoids the use of terms like "subject" and "object", which are not stable concepts from language to language. Moreover, it avoids the terms "agent" and "patient", which are semantic roles that do not correspond consistently to particular arguments. For instance, the A might be an experiencer or a source, semantically, not just an agent.
The relationship between ergative and accusative systems can be schematically represented as the following:
The following Basque examples demonstrate ergative–absolutive case marking system:13
gizona-∅
the.man-ABS
S
etorri da
has arrived
VERBintrans
gizona-∅ {etorri da}
the.man-ABS {has arrived}
S VERBintrans
'The man has arrived.'
gizona-k
the.man-ERG
A
mutila-∅
boy-ABS
O
ikusi du
saw
VERBtrans
gizona-k mutila-∅ {ikusi du}
the.man-ERG boy-ABS saw
A O VERBtrans
'The man saw the boy.'
In Basque, gizona is "the man" and mutila is "the boy". In a sentence like mutila gizonak ikusi du, you know who is seeing whom because -k is added to the one doing the seeing. So the sentence means "the man saw the boy". If you want to say "the boy saw the man", add the -k instead to the word meaning "the boy": mutilak gizona ikusi du.
With a verb like etorri, "come", there's no need to distinguish "who is doing the coming", so no -k is added. "The boy came" is mutila etorri da.
Japanese – by contrast – marks nouns by following them with different particles which indicate their function in the sentence:
kodomo ga
child NOM
tsuita
arrived
{kodomo ga} tsuita
{child NOM} arrived
'The child arrived.'
otoko ga
man NOM
kodomo o
child ACC
mita
{otoko ga} {kodomo o} mita
{man NOM} {child ACC} saw
'The man saw the child.'
In this language, in the sentence "the man saw the child", the one doing the seeing ("man") may be marked with ga, which works like Basque -k (and the one who is being seen may be marked with o). However, in sentences like "the child arrived" ga can still be used even though the situation involves only a "doer" and not a "done-to". This is unlike Basque, where -k is completely forbidden in such sentences.
Dixon, R. M. W. (1994). Ergativity. Cambridge University Press. /wiki/Robert_M._W._Dixon ↩
Comrie, Bernard. (1978). Ergativity. In W. P. Lehmann (Ed.), Syntactic typology: Studies in the phenomenology of language (pp. 329–394). Austin: University of Texas Press. /wiki/Bernard_Comrie ↩
Suda, Junichi (2025). "The Late-Klimov Model for Typological Classification of Active, Ergative, and Nominative Languages ― Re-evaluation of the Five Macroroles Model, et al". Typological Studies (7): 83–107. https://www.academia.edu/128211811/The_Late_Klimov_Model_for_Typological_Classification_of_Active_Ergative_and_Nominative_Languages_Re_evaluation_of_the_Five_Macroroles_Model_et_al ↩
Bickel, B. & Nichols, J. (2009). Case marking and alignment. In A. Malchukov & A. Spencer (Eds.), The Oxford Handbook of Case (pp. 304-321). New York, NY: Oxford University Press. /wiki/Balthasar_Bickel ↩
Nichols, J. & Bickel, B. (2013). Locus of Marking in the Clause. In M. S. Dryer & M. Haspelmath (Eds.), The World Atlas of Language Structures Online. Retrieved from http://wals.info/chapter/23 /wiki/Johanna_Nichols ↩
Nichols, J. (1986). Head-marking and dependent-marking grammar. Language, 62(1), 56-119. ↩
Comrie, B. (2013). Alignment of Case Marking of Full Noun Phrases. In M. S. Dryer & M. Haspelmath (Eds.), The World Atlas of Language Structures Online. Retrieved from http://wals.info/chapter/98 /wiki/Bernard_Comrie ↩
Anderson, Stephen. (1976). On the notion of subject in ergative languages. In C. Li. (Ed.), Subject and topic (pp. 1–24). New York: Academic Press. ↩
Campbell, G. L. & King, G. (2011). The Routledge Concise Compendium of the World's Languages (2nd ed, p. 62). New York, NY: Routledge. ↩