{"id":"GRM-001","name":"Subject–verb number agreement","domain":"grammar","layer":"clause","strength":"hard_constraint","human_logic":"IF a finite clause has an expressed subject AND neither quoted dialect nor an agreement exception applies, THEN align the finite verb with the subject in number ELSE retain.","when":{"all":[{"path":"clause.subject","operator":"exists"},{"path":"clause.verb.finite","operator":"eq","value":true},{"not":{"path":"context.mode","operator":"eq","value":"quoted_dialect"}}]},"then":[{"action":"align","target":"clause.verb.number","value_from":"clause.subject.grammatical_number"}],"else":[{"action":"retain","target":"current_text","reason":"No triggering condition is present."}],"unless":[],"because":"Agreement helps readers identify the intended grammatical relation.","diagnostics":["Ignore nouns inside intervening prepositional phrases when identifying the head subject.","Evaluate collective nouns and notional agreement according to dialect and house style."],"examples":{},"source_ids":["BK-002","BK-004","BK-010","WEB-011"],"laka":{"smallest_sufficient_intervention":true,"primary_axes":["scope","depth","magnitude","reversibility"]},"requires_facts":["clause.subject","clause.verb.finite","context.mode"],"tests":[{"id":"TST-001","rule_id":"GRM-001","before":"The list of items are ready.","after":"The list of items is ready.","reason":"The head subject is singular.","assertion":{"if":{"path":"output","operator":"eq","value":"The list of items is ready."},"then":"pass","else":"review"}}],"sources":[{"id":"BK-002","title":"The Blue Book of Grammar and Punctuation","creator":"Jane Straus; Lester Kaufman","domain":"grammar_reference","type":"Book","note":"Accessible grammar, punctuation, examples, and exercises.","url":null},{"id":"BK-004","title":"English Grammar in Use","creator":"Raymond Murphy","domain":"learner_grammar","type":"Book","note":"Self-study explanations and practice for core English grammar.","url":null},{"id":"BK-010","title":"Practical English Usage","creator":"Michael Swan","domain":"usage_reference","type":"Book","note":"Advanced grammar and usage reference for learners and teachers.","url":null},{"id":"WEB-011","title":"Grammar, Punctuation, and Sentence Structure","creator":"Purdue Online Writing Lab","domain":"grammar_reference","type":"University writing resource","note":"Practical mechanics, clause, sentence, punctuation, and style guidance.","url":"https://owl.purdue.edu/owl/general_writing/index.html"}],"defined_in":{"file":"07-core-grammar-rules.json","title":"Core Grammar Rules","slug":"core-grammar-rules"}}