P30 · The "Going-to-Do" Tail and Three "Should-Do" Hats
Teacher notes / sources (students may skip)
Corresponds to: Perry Lesson XXX (§314–327) = SKT บทที่ 30 (Second half of W16). Sources: Perry §314–327 (spine, STATUS: entire book checked across 112 chunks, zero residual flags, reliable). SKT vol. 16–30 OCR quality is poor, never quoted from the original (same precedent as P16/P17); Thai terminology omitted this lesson, Perry taken as the standard. Core idea: the verb's two "extension attachments" issued together, for the first time — the "going-to-do" tail -tum (attached to a verb = "to see / to go") + the "should-do" hat (put on = "must be ...ed, should be ...ed," three brims -तव्य/-अनीय/-य). Vocabulary is mostly old-friend verbs (paṭh/dṛś/kṛ/śru/bhū all recycled); the only new nouns carry strong anchors: nāṭaka/nṛtya/gīta/tapas. The term's final lesson: guru, kumāra, and devī, the three familiar characters, take their final bow together.
"No new Thai today — today we open up four Thai words you already know and show you the Sanskrit bones underneath:
สามารถ (Thai: "able to, capable") ← samartha (able, capable) — you say 'ทำได้/สามารถ' every day; this is the 'able' half of Sanskrit's 'able + to do.'
อรหันต์ (Thai: "arahant") ← arhant (an arahant) — literally 'one who deserves it,' from the verb arhati 'to deserve, be worthy of.' Today this verb is our 'the polite version of should.'
นาฏศิลป์/นาฏก (Thai: "performing arts/drama") ← nāṭaka (drama, play) — the นาฏศิลป์ ('performing arts') taught in schools has exactly this bone underneath.
การย์ (Thai: "duty, task, matter") ← kārya (a thing that should be done, a duty) — the การย์ in official Thai documents is precisely a noun made from today's 'should-do hat.'"
No new decoder rule this lesson — rule pool wrap-up. Instead, §5 "Use" takes today's four new words and sweeps back through already-taught old rules (a review day).
(The verbs are almost all old friends: avadat←vadati (P11 past tense), icchāmi←icchati (P11's aicchat, same root), nṛtyati (new, strong anchor นฤตย์), draṣṭum←dṛś (see, recycling the same-meaning root as paśyati). Cognate-recognition points per sentence: ๒ นาฏก/ทรรศนีย์; ๓ การย์/จาตุกรณีย์/อรหันต์; ๔ นฤตย์/คีต/ศรุติ; ๕ สุข/ประภพ. ๑ has a thin anchor (paṭh has no strong Thai cognate, pāṭha is this school's own name), backed up by §0's สามารถ/ตบะ. Classical Sanskrit direct-quotation phrases normally close with iti (recycled from P06); this lesson omits it to reduce friction, marking speech with quotation marks in the Chinese/English translation only.)
"The verb, up to now, can say 'he does, karoti' and 'he did yesterday, akarot.' Today it gets two more add-ons:"
Attachment one · the "going-to-do" tail -tum (= English "to do"):
"To say 'to go see, to go read' — take the verb's strong stem, attach -tum: dṛś→draṣṭum (to see), paṭh→paṭhitum (to read, with an extra i inserted), gam→gantum (to go), śru→śrotum (to hear).
It specifically pairs with three 'helper' verbs: icchati (want) / śaknoti (can, be able) / arhati (should, deserve) —
`nāṭakaṃ draṣṭum icchāmi` = I want to see the play; `gantuṃ śaknoti` = he can go; `draṣṭum arhasi` = you should go see it."
▸ Thai anchor: สามารถ (samartha, "able") is naturally built to pair with this tail — `samartho gantum` "has the means to go." When you say 'สามารถไป,' Sanskrit uses exactly this construction.
Attachment two · the "should-do" hat (put it on = "must be ...ed / should be ...ed," a passive-flavored sense of obligation):
"Take the same verb, swap its hat, and it flips from 'doing' to 'should be done.' Three brim-styles, all meaning the same thing — use whichever comes out smoother:
① The -तव्य hat (most regular, same procedure as the -tum tail): kṛ→kartavya, paṭh→paṭhitavya, śru→śrotavya, bhū→bhavitavya.
② The -अनीय hat (root takes its strong stem): kṛ→karaṇīya, dṛś→darśanīya (worth seeing), budh→bodhanīya.
③ The -य hat (shortest): kṛ→kārya, dā→deya, gai→geya (that ought to be sung)."
"Once the hat is on, the word behaves like an adjective, changing its brim to match whatever it describes: `pāṭhaḥ paṭhitavyaḥ` (lesson-masc · should-be-read), `gītaṃ śrotavyam` (song-neut · should-be-heard)."
▸ One √kṛ, three hats side by side (this lesson's centerpiece contrast): kārya (-य)/kartavya (-तव्य)/karaṇīya (-अनीय) — all mean "should be done." Story sentence ๓ lines up two side by side: `kāryaṃ ... karaṇīyam` = kārya used as a noun, "the task," as subject, karaṇīya as the predicate, "(should be) done." ▸ Thai anchor: การย์←kārya, จาตุกรณีย์←catur-karaṇīya (the king's four duties), ทรรศนีย์←darśanīya (worth a look) — the -अनीय hat is alive and well in modern Thai.
Building block (use-first, analyze-later — connective set): tu (but) / prathamam (first) / tataḥ (then) / ca (and).
`paṭhitavyaṃ prathamam, tataḥ nāṭakam` = read first, then watch the play — sequence words string the day's two events into one.
Farewell sentence (§327 special feature · for feeling only): `adya sarvaiḥ sukhibhir bhavitavyam` = "Today, everyone should be happy."
"This is a subjectless 'should-do' hat: it doesn't say 'who is happy' — it uses the instrument-hat 'by everyone' + the neuter bhavitavyam = 'happiness should be brought about (by everyone).' Learn the whole sentence as one chunk first, as the term's farewell."
- "The 'going-to-do' tail -tum: verb's strong stem + -tum (most consonant-final roots insert i: paṭhitum). Pairs specifically with icchati (want) / śaknoti (can) / arhati (should)."
- "The 'should-do' hat, three brims: -तव्य (most regular) / -अनीय (root's strong stem) / -य (shortest) — all mean 'should be ...ed'; once on, it behaves like an adjective, its brim changing with what it describes."
- "One-root-three-hats memory anchor: kārya · kartavya · karaṇīya = three ways of writing 'that which should be done.' Both การย์ and จาตุกรณีย์ are alive in Thai."
- "arhati = the polite 'should' = the root behind Thai's อรหันต์ ('one who deserves it'). `... draṣṭum arhasi` = you should go see it (a courteous suggestion)."
Story's five sentences, both versions; attachment slices: draṣṭum/paṭhitum/gantum/śrotum (four -tum tails in a row); 🔇kārya↔kartavya🔇↔karaṇīya (one root, three hats, slow comparative read); `sarvaiḥ sukhibhir bhavitavyam` (the §327 farewell sentence, as one block). Sandhi slice: kumāro 'vadat (aḥ+a→o+ऽ)/gurur avadat (uḥ+vowel→ur)/tato draṣṭum (aḥ+voiced→o). Native-speaker sentence layer: see 眞人原句池-RSS-L1-6 — "want/can/should + go-to-do" sentence patterns to be linked in first (sāmārtha/icchati are everyday high-frequency).
(Teacher's reference notes: kṛtya (กฤตย, that which should be done), darśanīya (ทรรศนีย์, worth seeing, a living fossil of the -अनीय hat), samāja (assembly, Perry word-list; note: Thai สมาคม actually derives from समागम samāgama, not from samāja, see metadata), tāpasa (ดาบส, an ascetic), vapus (วปุ, body, recycled from the as/us-stem in P21), śruti (ศรุติ, that which is heard) — for decode-and-recycle and syntax extension use, not entering the story for now. Perry §320–322's three infinitive cases (accusative/dative/genitive) and quasi-passive usage (`na avagantuṃ śakyate`, "cannot be understood") left for the teacher to cover optionally.)
This lesson is the second half of W16, the very last lesson of the term: it no longer bridges forward to a new crystallization lesson, but instead collects everything — after passing the four-gate check, it's recommended to hold a "wrap-up review" session that runs through the full table of the three "should-do hats" (-तव्य/-अनीय/-य × three genders × brims) together with the -tum tail's pairing patterns with icchati/śaknoti/arhati, along with every Decoder rule already amortized (L00–P30) in one continuous sweep, closing with the three old characters guru, kumāra, and devī delivering their "should-do hat" farewell lines.