Ergativity & Morphosyntactic Alignment: Conlang Evolution Guide

Morphosyntactic alignment determines how languages mark grammatical roles of sentence participants. Verbs are transitive (requiring objects) or intransitive (not requiring objects), with arguments labeled S (subject/intransitive), A (agent/transitive), and P (patient/transitive). Languages fall into two main systems: nominative-accusative (English, most languages) marks P with accusative case while grouping S and A; ergative-absolutive (Georgian, Basque) marks A with ergative case while grouping S and P. Languages use voice constructions: passive promotes P to subject in accusative systems; antipassive eliminates P in ergative systems. Natural languages exhibit complex patterns: split-ergative languages combine accusative and ergative features based on animacy, tense, or clause type; split-S systems categorize intransitive verbs by volition; fluid-S systems adjust marking contextually; tense-based splits treat past as ergative and present/future as accusative; morphosyntactic splits separate morphological and syntactic alignment; clausal splits apply different alignments to main versus subordinate clauses. No language is fully ergative—all exhibit some accusativity.

Morphosyntactic alignment governs how grammatical roles are marked across verb types. Nominative-accusative alignment (used by most languages including English) treats intransitive subjects identically to transitive agents. Ergative-absolutive alignment (25% of world languages) treats intransitive subjects identically to transitive patients. Active-stative alignment distinguishes active intransitive verbs (agent-like marking) from stative intransitive verbs (patient-like marking). Split-S and Fluid-S systems allow subjects to shift between agent/patient roles contextually. No language is fully ergative—some elements always appear nominative-accusative. This alignment system fundamentally shapes how languages express grammatical relationships.

This section contrasts two major case alignment strategies. The nominative-accusative system (used in English, Spanish, French, German) groups subject and agent together (nominative case) while marking the patient separately (accusative). The ergative-absolutive system reverses this pattern, grouping subject and patient together (absolutive) while marking the agent separately (ergative). Both systems mark only one argument type differently, creating mirror-image relationships. The choice between systems is arbitrary and doesn't reflect linguistic correctness.

Grammatical cases are morphological markers that indicate the syntactic function of nouns within a sentence, with the nominative-accusative system being the most common alignment type where the nominative marks the subject (who performs the action) and the accusative marks the direct object (who receives the action directly). This system is used in many Western languages including German, Latin, Greek, and Arabic, where nouns change their form (decline) depending on their grammatical role in the sentence, allowing for more flexible word order compared to languages like Spanish that rely primarily on word position and prepositions to express grammatical relationships.

Languages express relationships between words through two main strategies. First, word order: English uses SVO (Subject-Verb-Object), Hindi uses SOV (Subject-Object-Verb), and Irish uses VSO (Verb-Subject-Object). Second, morphological marking: languages add morphemes to indicate subject vs. object, as in Latin where hospes leporem videt ('host sees rabbit') differs from hospitem lepus videt ('rabbit sees host'). Signed languages like ASL use spatial referencing. English retains traces of morphological strategies in phrases like 'I see them.' These strategies allow languages to convey who did what to whom consistently.

Languages express grammatical relations (who does what to whom) through four main strategies: word order, case marking, head marking, and adpositions. Word order relies on position alone. Case marking uses affixes on nouns to indicate their role. Head marking changes the verb form to show relations. Adpositions use separate words before or after phrases. Each strategy affects how sentences are structured and parsed.

Case-marking is a fundamental grammatical strategy used by approximately 60% of languages to specify grammatical roles in phrases. Unlike verb agreement, case-marking appends markers directly to nouns to indicate their role (subject, direct object, indirect object, or adpositional object). Case morphology typically evolves from adpositions, adverbs, or demonstratives that become dedicated affixes. The number of cases varies dramatically, from 2-3 in Persian/Romanian to over a dozen in Finnish/Hungarian. Core case distinctions include nominative (unmarked subject), accusative (direct object), genitive (possession), dative (indirect object/beneficiary), instrumental (means), locative (location), and ablative (movement away). These cases form a hierarchy where languages typically have all higher-ranked cases if they possess lower ones. Case systems exhibit remarkable semantic complexity: single markers often encode multiple roles (Manchu's genitive/instrumental and locative/dative), quirky subjects show non-nominative marking for low-agency entities, and differential object marking varies by animacy/definiteness. Case markers appear as affixes (most common) or separate particles, undergoing phonological reduction over time. New adpositions emerge from possessive nouns or verbs, sometimes creating compound case markers. Case loss occurs when phonological changes cause markers to merge—Latin's locative case disappeared because it became identical to genitive/dative. When entire case systems collapse (Romance languages, English), languages compensate with stricter word order and retained verb agreement. For naturalistic conlang design, establish lexical sources for each case, determine their implicational meanings, and ensure compatibility with other role-marking strategies.

From a syntactic standpoint, there's a reasonably clear distinction between structural and inherent cases in terms of contexts of alternation and ability to undergo movement. The morphological differences are more blended because dependent cases behave syntactically like structural cases but morphologically more like inherent cases. This creates a gradient rather than a clear bifurcation. Agreement can be sensitive to case morphology and correlate with syntactic things like movement. Three options for agreement's location: (1) Agreement is morphological (late in syntax after spell-out); (2) Agreement creation is syntactic but feature transfer happens later in morphology; (3) Agreement is always syntactic, but case discrimination works because you can discriminate between different flavors of KP and DP. The third option makes a clear prediction: case-discriminating agreement should only care about syntactic differences.

Grammatical case marking is a linguistic strategy used by languages to distinguish between subjects and objects in transitive clauses; the three main strategies include fixed word order (where subject precedes verb and object follows, as in English), person marking on verbs (where subject or object person is indicated through verb conjugation, as in Spanish), and case marking using endings (where nouns receive specific morphological markers to indicate their grammatical role). The world's languages predominantly use either the nominative-accusative system (most common, found in Indo-European languages like German and English) or the ergative-absolutive system (second most common, found in Basque and concentrated in Australia and New Guinea), with some languages combining elements of both systems.

This segment covers passive voice construction (will be asked to), nominalization (votes from verb to noun), and noun clause introduction (who received...). The instructor explains how complex sentence structures require understanding grammatical transformations and how different clause types function within sentences.

Classic prose avoids clichés because they force readers to process words as meaningless or create mixed metaphors. It also avoids excessive metaconcepts (approach, framework, paradigm, strategy) that focus on conceptual tools rather than the world itself. Nominalization—turning verbs into nouns like 'make an appearance' instead of 'appear'—creates 'zombie nouns' that lumber across pages without conscious agents. The passive voice is not inherently bad—it serves legitimate purposes when the done-to or acted-upon entity is the reader's focus. English syntax requires word order to simultaneously express who did what to whom and present information in absorbable order. The passive allows writers to vary this order, starting with recipients rather than actors. Good writers narrate forward with protagonists; bad writers work backward from their own knowledge, using passives to hide that they're beginning with outcomes and adding causes as afterthoughts.

Passive voice (مبني للمجهول) is a grammatical construction where the subject (فاعل) is unknown or not mentioned. The verb is conjugated to indicate the action is being received rather than performed by a known subject. For present tense verbs, add a damma (ضمة) to the beginning and a fatha (فتحة) before the last letter. For past tense verbs, add a damma (ضمة) to the beginning and a kasra (كسرة) before the last letter. The nominative agent (نائب الفاعل) takes the place of the subject and is always in the nominative case (مرفوع) marked by a damma on its last letter. To convert passive to active voice, add an appropriate subject (فاعل) to the verb. When converting passive to active voice, the verb must agree in gender with the subject. For feminine subjects, add a taa tanween (تاء تنوين) to the end of past tense verbs.

Nominalization (la nominalisation) is the grammatical process of converting a sentence containing a verb (active sentence) into a sentence containing a noun (nominal sentence), which requires adding specific suffixes to the verb such as -tion, -ion, -ment, or -aison to transform the verb into a noun form.

This segment covers advanced syntactic analysis techniques for complex sentences. The instructor explains how to distinguish between 'complemento nominal' (nominal complement) and 'adjunto adnominal' (adnominal adjunct) by analyzing the semantic relationship: complements represent the patient of the abstract noun's action, while adjuncts represent the agent or possessor. The segment covers how to identify identical syntactic functions when the same word appears multiple times in a sentence. The instructor also covers passive voice constructions, explaining that the pronoun 'se' cannot simultaneously function as both a passive marker and an indicator of subject indeterminacy. The segment covers adverbial conjunctions like 'não só... mas também' expressing additive relationships between clauses. The instructor also covers nominalization in Portuguese, involving the transformation of verbs into nouns (substantivos abstratos) or adjectives, demonstrating how grammatical transformations can create more formal or literary expressions.