Fill coverage gaps in chapters 1-11

Audited each chapter file against actual LLPSI Familia Romana content
using parallel reviewers (Claude general-purpose subagents, codex, gemini).
Each chapter gained missing vocabulary, grammar points, common-error
patterns, and exercise types. ~190 lines added across 11 files.

Highlights per chapter:
- c1: geography proper nouns, -us fem. exceptions, num-question answer pattern
- c2: -er paradigm contrast (puer/vir/liber), -que rewrite drill
- c3: interrog. vs. relative quem, neque rewrite
- c4: nullus/UNUS NAUTA, -ius vocative, eius/suus contrast
- c5: relative pron. (nom.), suus agreement, -ae ambiguity
- c6: passus 4th-decl preview, mille/milia, autem postpositive
- c7: cui drill, plenus + gen., quod (because/relative/interrog.) trap
- c8: hic/ille discourse force, UNUS NAUTA class, quantus/quot trap
- c9: stem recovery from gen., ipse emphasis target, sub + abl. for location
- c10: fera vs. ferus, abesse/adesse/ire infinitives, quia/quod synonymy
- c11: full posse paradigm, dat. of reference (mihi dolet), gaudere syntax

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

llpsi-c10.md

@@ -13,7 +13,7 @@ Topic argument supported (e.g. `/llpsi-c10 infinitive`, `/llpsi-c10 acc-inf`, `/
 
 **Nouns — 2nd decl.**: *asinus -ī* m. (ass); *deus -ī* m. (god); *nīdus -ī* m. (nest); *rāmus -ī* m. (branch); *folium -ī* n. (leaf); *ōvum -ī* n. (egg); *pullus -ī* m. (chick, young); *petasus -ī* m. (winged hat).
 
-**Nouns — 1st decl.**: *bēstia -ae* f. (beast); *aquila -ae* f. (eagle); *āla -ae* f. (wing); *cauda -ae* f. (tail); *anima -ae* f. (breath, soul); *pila -ae* f. (ball).
+**Nouns — 1st decl.**: *bēstia -ae* f. (beast); *fera -ae* f. (wild animal — distinct from adj. *ferus*); *aquila -ae* f. (eagle); *āla -ae* f. (wing); *cauda -ae* f. (tail); *anima -ae* f. (breath, soul); *pila -ae* f. (ball).
 
 **Adjectives**: *ferus -a -um* (wild); *vīvus -a -um* (alive) ↔ *mortuus -a -um* (dead); *crassus -a -um* (thick, fat) ↔ *tenuis -e* (thin — note 3rd-decl. adj., -is/-e endings); *perterritus -a -um* (terrified).
 
@@ -40,6 +40,8 @@ Topic argument supported (e.g. `/llpsi-c10 infinitive`, `/llpsi-c10 acc-inf`, `/
 - *posse* (to be able): *potest / possunt.*
 - *velle* (to want): *vult / volunt.* (Only 3sg/3pl shown.)
 - *esse* (to be) → infinitive *esse*; **but** *ēsse* = "to eat" (long ē — same form as old "edere" contracted).
+- *abesse* (to be away — inf. of *abest/absunt*); *adesse* (to be present — inf. of *adest/adsunt*).
+- *īre* (to go — inf. of *it/eunt*).
 
 **Particles**: *enim* (postpositive, "for"); *ergō* (therefore); *cum* + indic. (when); *quod* (because); *necesse est* + dat. + inf. (it is necessary for).
 
@@ -93,6 +95,10 @@ Topic argument supported (e.g. `/llpsi-c10 infinitive`, `/llpsi-c10 acc-inf`, `/
 
 10. ***necesse est*** + dat. of person + infinitive: "it is necessary for X to ___." *Spīrāre necesse est hominī.* "Breathing is necessary for a human."
 
+11. **Infinitive as subject**: the inf. itself can be the grammatical subject of *est* / *necesse est*. *Vīvere necesse est.* ("To live is necessary.") *Errāre hūmānum est.*
+
+12. ***cum*** + indic. as temporal "when/whenever" — distinct from *cum* + abl. preposition ("with"). *Cum sōl lūcet, avēs canunt.*
+
 ## Common error patterns
 
 - **Confusing infinitive endings -ere vs. -ēre** (3rd vs. 2nd conj.): *vidēre* (2nd, long ē) vs. *vīvere* (3rd, short e). Without macrons, only memory tells you. *vidēre potest, vīvere potest.*
@@ -105,6 +111,9 @@ Topic argument supported (e.g. `/llpsi-c10 infinitive`, `/llpsi-c10 acc-inf`, `/
 - ***homō* declension**: *homō, hominis* — student writes *homonem* — wrong; acc. is *hominem* (vowel change in stem). Pl. *hominēs, hominum.*
 - ***quod* (because) vs. *quod* (n. relative)**: same form. Context: *quod* + clause with finite verb usually = "because"; *quod* with antecedent noun = relative.
 - **Translating "wants" with present of *amāre***: *Iūlia lūdere amat* — wrong; use *vult: Iūlia lūdere vult.*
+- **Acc. of *āer***: students assume 1st-decl. *āeram* — wrong; *āēr* is 3rd decl., acc. *āerem*.
+- **Mixing *volāre* (to fly) with *velle* (to want)** because of similar *vol-* root: *aquila volat* (flies) vs. *aquila volat capere* — wrong; "wants to" is *vult* (*aquila capere vult*).
+- ***quia* vs. *quod***: both = "because" and are largely interchangeable; don't treat them as different in meaning.
 
 ## Exercise menu
 
@@ -118,6 +127,9 @@ Topic argument supported (e.g. `/llpsi-c10 infinitive`, `/llpsi-c10 acc-inf`, `/
 8. **3rd-decl. forms (more)**: "Decline *homō* sg + pl." → *homō, hominem, hominis, hominī, homine; hominēs, hominēs, hominum, hominibus, hominibus.* Same for *leō, vōx, pēs, mare, animal.*
 9. **PENSVM C Q&A**: "Quae bēstiae ōva pariunt?" → *Avēs (ōva pariunt).* "Cūr rāmus Quīntum sustinēre nōn potest?" → *Quia rāmus tenuis est et Quīntus crassus est.* "Quid agit Mercurius?" → *Mercurius volat / imperia deōrum (ad hominēs) portat.*
 10. **Translate (using acc.+inf.)**: "Marcus sees Quintus fall to the ground." → *Mārcus Quīntum ad terram cadere videt.* "Aemilia sees Quintus being placed on the bed." → *Aemilia Quīntum in lectō pōnī videt / aspicit.* "Julius hears the boy shouting." → *Iūlius puerum clāmāre audit.*
+11. **PENSVM B cloze**: contextual vocab fills from the chapter. "Aquila est avis magna quae ___ habet et ___ potest." → *ālās, volāre.* "Piscēs in ___ natant; in āere spīrāre nōn ___." → *aquā / marī, possunt.*
+12. ***quia* ↔ *quod* swap**: convert *quia*-clause to *quod*-clause (and vice versa). "Canis volāre nōn potest, *quia* ālās nōn habet." → *...quod ālās nōn habet.* "Quīntus cadit *quod* rāmus tenuis est." → *...quia rāmus tenuis est.*
+13. **Conjugation ID by stress / vowel length**: pronounce inf. with correct stress; mark macron. "*videre* — mark macron + conj.?" → *vidēre*, 2nd (long ē, stressed). "*vivere*?" → *vīvere*, 3rd (short e, antepenult stress). Cycle: *movēre / pōnere, sustinēre / cadere, audēre / ascendere*.
 
 ## Session start