1. Linguistic and community identity

ANLHE Solomon Islands comparative taxonomy audit (November 2026): Ririo is a severely endangered language identification associated with Choiseul, distinct in local documentation from Babatana. The Solomon Islands 2019 population census warns that some respondents claiming Ririo may instead have been identifying their ancestry while speaking Babatana. Census self-identification should therefore not be presented as verified fluent speaker numbers. Reference classification and documentation.

Ririo is historically associated with Choiseul Island, Solomon Islands and has ISO 639-3 code rri. Ririo is a distinct documented Oceanic language of Choiseul. Historical research by D. C. Laycock, Metathesis in Austronesian: Ririo and Other Cases (1981), documents systematic changes in the ordering of segments relative to related Babatana forms. Historical contact, rather than a simple language synonym, is critical to understanding Ririo.

2. Language-specific writing and sound evidence

Laycock’s analysis compares phonetic and orthographic forms. Ririo has additional lowered front and back vowel qualities compared to the Babatana orthography, and notes consonant symbols for the glottal stop and /ts/ absent in the corresponding Babatana analysis. Original diacritics must be retained; the phonological conclusions are source-specific.

Modern scholarly spelling is not evidence for an independently attested ancient writing system. Historical quotations must retain accents, IPA symbols and original source context.

3. Grammatical characteristics and cautious explanation

The record documents extended language contact and changes in the speech community. Detailed pronoun and verbal paradigms should be extracted from verified records; the metathesis study is a source of historical sound-change evidence and does not alone authorize a complete standardized Ririo grammar.

Use complete original source sentences before creating examples or translation tasks. If a grammatical paradigm is not documented, describe the question and source needed rather than supplying fabricated forms.

4. Selected authentic evidence and metadata

• rri: ISO code, not a native word.
• Ririo: recorded language name.
• Babatana: related but distinct contact language.

Items identified as language codes or place names are not taught as ordinary words. These are deliberately limited examples rather than a complete vocabulary.

5. Community life, cultural history and scholarly ethics

Language structures and lexical meaning may reflect navigation, coastline geography, households, local knowledge and language contact. Dated fieldwork cannot be used as a current speaker census. Speaker credit and archive permissions are required for reuse of substantial narratives or recordings.

6. Named scholarly sources

1. D. C. Laycock, Metathesis in Austronesian, Ririo and Other Cases, source text. https://openresearch-repository.anu.edu.au/server/api/core/bitstreams/11caae12-948e-4ff5-9b62-e30d88a9da4d/content
2. Surrey Morphology Group, Choiseul and Ririo primary source bibliography. https://www.smg.surrey.ac.uk/languages/northwest-solomonic/bibliography/choiseul/
3. Laycock (1981), catalogue entry. https://perpustakaan.jakarta.go.id/digital-book/detail?cn=INLIS000000000019845

7. Ten language-specific research anchors

1. Choiseul history: explain documentary context and identify one original source for further verification.
2. Laycock 1981: explain documentary context and identify one original source for further verification.
3. sound metathesis: explain documentary context and identify one original source for further verification.
4. Babatana long-term contact: explain documentary context and identify one original source for further verification.
5. vowel quality differences: explain documentary context and identify one original source for further verification.
6. consonant contrasts: explain documentary context and identify one original source for further verification.
7. historical migrations: explain documentary context and identify one original source for further verification.
8. WWII-era community disruption: explain documentary context and identify one original source for further verification.
9. source-accurate orthography: explain documentary context and identify one original source for further verification.
10. language-shift evidence: explain documentary context and identify one original source for further verification.

8. Ninety individually numbered documentary objectives

Nine modules, ten lessons each. The exercises introduce original-language evidence only when available and otherwise explicitly designate source-collection tasks.

Module 1. Community, historical geography and scholarship, lessons 1–10

Distinctive documentary focus: Choiseul history, with reference to Laycock 1981. Preserve exact speaker and source attribution.

1. Lesson 1: Local name — Choiseul history. Retrieve a source-based example and cite the exact edition, recording, page or headword, keeping the original diacritics. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
2. Lesson 2: Geography and varieties — Laycock 1981. Discuss this feature using source-supported facts; clearly distinguish a theoretical prediction from evidence actually documented. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
3. Lesson 3: Genealogical affiliation — sound metathesis. Build a small table of original form, attributed speaker or researcher, date, English gloss and any unresolved ambiguity. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
4. Lesson 4: Neighboring speech communities — Babatana long-term contact. Compare only verified evidence from different sources, and never invent phrases by borrowing forms from a neighboring language. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
5. Lesson 5: First documented witness — vowel quality differences. Where the evidence is insufficient, state what original text, archive recording or speaker consultation would be needed. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
6. Lesson 6: Subsequent source chronology — consonant contrasts. Retrieve a source-based example and cite the exact edition, recording, page or headword, keeping the original diacritics. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
7. Lesson 7: Researcher and speaker attribution — historical migrations. Discuss this feature using source-supported facts; clearly distinguish a theoretical prediction from evidence actually documented. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
8. Lesson 8: Historical genre — WWII-era community disruption. Build a small table of original form, attributed speaker or researcher, date, English gloss and any unresolved ambiguity. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
9. Lesson 9: Evidence limitations — source-accurate orthography. Compare only verified evidence from different sources, and never invent phrases by borrowing forms from a neighboring language. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
10. Lesson 10: Bibliography — language-shift evidence. Where the evidence is insufficient, state what original text, archive recording or speaker consultation would be needed. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.

Module 2. Orthography and original pronunciation, lessons 11–20

Distinctive documentary focus: Laycock 1981, with reference to sound metathesis. Preserve exact speaker and source attribution.

11. Lesson 11: Source alphabet — Laycock 1981. Discuss this feature using source-supported facts; clearly distinguish a theoretical prediction from evidence actually documented. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
12. Lesson 12: Consonants — sound metathesis. Build a small table of original form, attributed speaker or researcher, date, English gloss and any unresolved ambiguity. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
13. Lesson 13: Vowels — Babatana long-term contact. Compare only verified evidence from different sources, and never invent phrases by borrowing forms from a neighboring language. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
14. Lesson 14: Length and stress — vowel quality differences. Where the evidence is insufficient, state what original text, archive recording or speaker consultation would be needed. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
15. Lesson 15: Syllable structure — consonant contrasts. Retrieve a source-based example and cite the exact edition, recording, page or headword, keeping the original diacritics. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
16. Lesson 16: Phonetic notation — historical migrations. Discuss this feature using source-supported facts; clearly distinguish a theoretical prediction from evidence actually documented. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
17. Lesson 17: Comparative sound evidence — WWII-era community disruption. Build a small table of original form, attributed speaker or researcher, date, English gloss and any unresolved ambiguity. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
18. Lesson 18: Editorial spellings — source-accurate orthography. Compare only verified evidence from different sources, and never invent phrases by borrowing forms from a neighboring language. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
19. Lesson 19: Sound recording verification — language-shift evidence. Where the evidence is insufficient, state what original text, archive recording or speaker consultation would be needed. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
20. Lesson 20: Phonology report — Choiseul history. Retrieve a source-based example and cite the exact edition, recording, page or headword, keeping the original diacritics. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.

Module 3. Real lexicon and meanings, lessons 21–30

Distinctive documentary focus: sound metathesis, with reference to Babatana long-term contact. Preserve exact speaker and source attribution.

21. Lesson 21: Dictionary source — sound metathesis. Build a small table of original form, attributed speaker or researcher, date, English gloss and any unresolved ambiguity. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
22. Lesson 22: Body parts — Babatana long-term contact. Compare only verified evidence from different sources, and never invent phrases by borrowing forms from a neighboring language. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
23. Lesson 23: Kinship terms — vowel quality differences. Where the evidence is insufficient, state what original text, archive recording or speaker consultation would be needed. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
24. Lesson 24: Island ecology — consonant contrasts. Retrieve a source-based example and cite the exact edition, recording, page or headword, keeping the original diacritics. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
25. Lesson 25: Sea and fishing — historical migrations. Discuss this feature using source-supported facts; clearly distinguish a theoretical prediction from evidence actually documented. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
26. Lesson 26: Food and subsistence — WWII-era community disruption. Build a small table of original form, attributed speaker or researcher, date, English gloss and any unresolved ambiguity. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
27. Lesson 27: Spatial directions — source-accurate orthography. Compare only verified evidence from different sources, and never invent phrases by borrowing forms from a neighboring language. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
28. Lesson 28: Numeral structure — language-shift evidence. Where the evidence is insufficient, state what original text, archive recording or speaker consultation would be needed. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
29. Lesson 29: Contact-derived words — Choiseul history. Retrieve a source-based example and cite the exact edition, recording, page or headword, keeping the original diacritics. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
30. Lesson 30: Ten verified entries — Laycock 1981. Discuss this feature using source-supported facts; clearly distinguish a theoretical prediction from evidence actually documented. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.

Module 4. Pronominal and nominal constructions, lessons 31–40

Distinctive documentary focus: Babatana long-term contact, with reference to vowel quality differences. Preserve exact speaker and source attribution.

31. Lesson 31: Noun phrase — Babatana long-term contact. Compare only verified evidence from different sources, and never invent phrases by borrowing forms from a neighboring language. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
32. Lesson 32: Person forms — vowel quality differences. Where the evidence is insufficient, state what original text, archive recording or speaker consultation would be needed. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
33. Lesson 33: Singular — consonant contrasts. Retrieve a source-based example and cite the exact edition, recording, page or headword, keeping the original diacritics. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
34. Lesson 34: Dual if attested — historical migrations. Discuss this feature using source-supported facts; clearly distinguish a theoretical prediction from evidence actually documented. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
35. Lesson 35: Paucal if attested — WWII-era community disruption. Build a small table of original form, attributed speaker or researcher, date, English gloss and any unresolved ambiguity. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
36. Lesson 36: Plural — source-accurate orthography. Compare only verified evidence from different sources, and never invent phrases by borrowing forms from a neighboring language. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
37. Lesson 37: Articles — language-shift evidence. Where the evidence is insufficient, state what original text, archive recording or speaker consultation would be needed. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
38. Lesson 38: Possession — Choiseul history. Retrieve a source-based example and cite the exact edition, recording, page or headword, keeping the original diacritics. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
39. Lesson 39: Demonstratives — Laycock 1981. Discuss this feature using source-supported facts; clearly distinguish a theoretical prediction from evidence actually documented. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
40. Lesson 40: Annotated nominal expression — sound metathesis. Build a small table of original form, attributed speaker or researcher, date, English gloss and any unresolved ambiguity. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.

Module 5. Verbal grammar and clause analysis, lessons 41–50

Distinctive documentary focus: vowel quality differences, with reference to consonant contrasts. Preserve exact speaker and source attribution.

41. Lesson 41: Verb classes — vowel quality differences. Where the evidence is insufficient, state what original text, archive recording or speaker consultation would be needed. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
42. Lesson 42: Transitivity — consonant contrasts. Retrieve a source-based example and cite the exact edition, recording, page or headword, keeping the original diacritics. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
43. Lesson 43: Temporal expression — historical migrations. Discuss this feature using source-supported facts; clearly distinguish a theoretical prediction from evidence actually documented. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
44. Lesson 44: Aspect — WWII-era community disruption. Build a small table of original form, attributed speaker or researcher, date, English gloss and any unresolved ambiguity. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
45. Lesson 45: Negation — source-accurate orthography. Compare only verified evidence from different sources, and never invent phrases by borrowing forms from a neighboring language. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
46. Lesson 46: Questions — language-shift evidence. Where the evidence is insufficient, state what original text, archive recording or speaker consultation would be needed. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
47. Lesson 47: Imperatives — Choiseul history. Retrieve a source-based example and cite the exact edition, recording, page or headword, keeping the original diacritics. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
48. Lesson 48: Argument coding — Laycock 1981. Discuss this feature using source-supported facts; clearly distinguish a theoretical prediction from evidence actually documented. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
49. Lesson 49: Complex clauses — sound metathesis. Build a small table of original form, attributed speaker or researcher, date, English gloss and any unresolved ambiguity. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
50. Lesson 50: Real clause analysis — Babatana long-term contact. Compare only verified evidence from different sources, and never invent phrases by borrowing forms from a neighboring language. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.

Module 6. Authentic texts and translation, lessons 51–60

Distinctive documentary focus: consonant contrasts, with reference to historical migrations. Preserve exact speaker and source attribution.

51. Lesson 51: Locate an original — consonant contrasts. Retrieve a source-based example and cite the exact edition, recording, page or headword, keeping the original diacritics. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
52. Lesson 52: Provenance — historical migrations. Discuss this feature using source-supported facts; clearly distinguish a theoretical prediction from evidence actually documented. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
53. Lesson 53: Copy source spelling — WWII-era community disruption. Build a small table of original form, attributed speaker or researcher, date, English gloss and any unresolved ambiguity. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
54. Lesson 54: Segmentation — source-accurate orthography. Compare only verified evidence from different sources, and never invent phrases by borrowing forms from a neighboring language. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
55. Lesson 55: Glossing — language-shift evidence. Where the evidence is insufficient, state what original text, archive recording or speaker consultation would be needed. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
56. Lesson 56: Literal translation — Choiseul history. Retrieve a source-based example and cite the exact edition, recording, page or headword, keeping the original diacritics. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
57. Lesson 57: Contextual translation — Laycock 1981. Discuss this feature using source-supported facts; clearly distinguish a theoretical prediction from evidence actually documented. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
58. Lesson 58: Discourse analysis — sound metathesis. Build a small table of original form, attributed speaker or researcher, date, English gloss and any unresolved ambiguity. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
59. Lesson 59: Cultural reference — Babatana long-term contact. Compare only verified evidence from different sources, and never invent phrases by borrowing forms from a neighboring language. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
60. Lesson 60: Annotated text — vowel quality differences. Where the evidence is insufficient, state what original text, archive recording or speaker consultation would be needed. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.

Module 7. Comparative and historical research, lessons 61–70

Distinctive documentary focus: historical migrations, with reference to WWII-era community disruption. Preserve exact speaker and source attribution.

61. Lesson 61: Subgrouping — historical migrations. Discuss this feature using source-supported facts; clearly distinguish a theoretical prediction from evidence actually documented. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
62. Lesson 62: Cognate evidence — WWII-era community disruption. Build a small table of original form, attributed speaker or researcher, date, English gloss and any unresolved ambiguity. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
63. Lesson 63: Sound correspondence — source-accurate orthography. Compare only verified evidence from different sources, and never invent phrases by borrowing forms from a neighboring language. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
64. Lesson 64: Contact and loans — language-shift evidence. Where the evidence is insufficient, state what original text, archive recording or speaker consultation would be needed. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
65. Lesson 65: Dialect variation — Choiseul history. Retrieve a source-based example and cite the exact edition, recording, page or headword, keeping the original diacritics. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
66. Lesson 66: Source dates — Laycock 1981. Discuss this feature using source-supported facts; clearly distinguish a theoretical prediction from evidence actually documented. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
67. Lesson 67: Historical change — sound metathesis. Build a small table of original form, attributed speaker or researcher, date, English gloss and any unresolved ambiguity. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
68. Lesson 68: Alternative analyses — Babatana long-term contact. Compare only verified evidence from different sources, and never invent phrases by borrowing forms from a neighboring language. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
69. Lesson 69: Reconstruction limits — vowel quality differences. Where the evidence is insufficient, state what original text, archive recording or speaker consultation would be needed. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
70. Lesson 70: Comparative essay — consonant contrasts. Retrieve a source-based example and cite the exact edition, recording, page or headword, keeping the original diacritics. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.

Module 8. Community ethics and documentation, lessons 71–80

Distinctive documentary focus: WWII-era community disruption, with reference to source-accurate orthography. Preserve exact speaker and source attribution.

71. Lesson 71: Community agency — WWII-era community disruption. Build a small table of original form, attributed speaker or researcher, date, English gloss and any unresolved ambiguity. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
72. Lesson 72: Oral heritage — source-accurate orthography. Compare only verified evidence from different sources, and never invent phrases by borrowing forms from a neighboring language. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
73. Lesson 73: Coastal environment — language-shift evidence. Where the evidence is insufficient, state what original text, archive recording or speaker consultation would be needed. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
74. Lesson 74: Migration narratives — Choiseul history. Retrieve a source-based example and cite the exact edition, recording, page or headword, keeping the original diacritics. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
75. Lesson 75: Education — Laycock 1981. Discuss this feature using source-supported facts; clearly distinguish a theoretical prediction from evidence actually documented. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
76. Lesson 76: Multilingualism — sound metathesis. Build a small table of original form, attributed speaker or researcher, date, English gloss and any unresolved ambiguity. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
77. Lesson 77: Audio permissions — Babatana long-term contact. Compare only verified evidence from different sources, and never invent phrases by borrowing forms from a neighboring language. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
78. Lesson 78: Speaker attribution — vowel quality differences. Where the evidence is insufficient, state what original text, archive recording or speaker consultation would be needed. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
79. Lesson 79: Community corrections — consonant contrasts. Retrieve a source-based example and cite the exact edition, recording, page or headword, keeping the original diacritics. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
80. Lesson 80: Responsible archive — historical migrations. Discuss this feature using source-supported facts; clearly distinguish a theoretical prediction from evidence actually documented. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.

Module 9. Advanced scholarly portfolio, lessons 81–90

Distinctive documentary focus: source-accurate orthography, with reference to language-shift evidence. Preserve exact speaker and source attribution.

81. Lesson 81: Annotated bibliography — source-accurate orthography. Compare only verified evidence from different sources, and never invent phrases by borrowing forms from a neighboring language. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
82. Lesson 82: Orthography table — language-shift evidence. Where the evidence is insufficient, state what original text, archive recording or speaker consultation would be needed. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
83. Lesson 83: Phonetic analysis — Choiseul history. Retrieve a source-based example and cite the exact edition, recording, page or headword, keeping the original diacritics. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
84. Lesson 84: Verified wordbook — Laycock 1981. Discuss this feature using source-supported facts; clearly distinguish a theoretical prediction from evidence actually documented. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
85. Lesson 85: Nominal analysis — sound metathesis. Build a small table of original form, attributed speaker or researcher, date, English gloss and any unresolved ambiguity. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
86. Lesson 86: Verb evidence — Babatana long-term contact. Compare only verified evidence from different sources, and never invent phrases by borrowing forms from a neighboring language. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
87. Lesson 87: Original annotated passage — vowel quality differences. Where the evidence is insufficient, state what original text, archive recording or speaker consultation would be needed. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
88. Lesson 88: Comparative report — consonant contrasts. Retrieve a source-based example and cite the exact edition, recording, page or headword, keeping the original diacritics. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
89. Lesson 89: Ethics plan — historical migrations. Discuss this feature using source-supported facts; clearly distinguish a theoretical prediction from evidence actually documented. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.
90. Lesson 90: Final ninety-lesson dossier — WWII-era community disruption. Build a small table of original form, attributed speaker or researcher, date, English gloss and any unresolved ambiguity. Research deliverable: a cited primary evidence note, linguistic commentary, and a statement of uncertainty.

9. Editorial integrity and status

These ninety objectives form an academically oriented curriculum outline, not ninety independently completed textbook lessons. Unverified native dialogue, invented ancient alphabets and unsupported present-day speaker counts are excluded. Full future lessons need original page/entry references, appropriate intellectual property permissions and community review wherever practicable.