महाभारतः mahābhārataḥ - book-6, chapter-8, verse-17

दश वर्षसहस्राणि तत्रायुर्भरतर्षभ ।
कालाम्ररसपीतास्ते नित्यं संस्थितयौवनाः ॥१७॥

17. daśa varṣasahasrāṇi tatrāyurbharatarṣabha ,
kālāmrarasapītāste nityaṁ saṁsthitayauvanāḥ.

17. daśa varṣasahasrāṇi tatra āyuḥ bharatarṣabha
kālāmrarasapītāḥ te nityaṃ saṃsthitayauvanāḥ

17. bharatarṣabha! tatra te daśa varṣasahasrāṇi āyuḥ.
te kālāmrarasapītāḥ nityaṃ saṃsthitayauvanāḥ

17. O best among the Bharatas, their lifespan (āyuḥ) there is ten thousand years. Having drunk the juice of the black mango, they remain perpetually youthful.

Words meanings summery:

• दश (daśa) - ten

• वर्षसहस्राणि (varṣasahasrāṇi) - thousands of years

• तत्र (tatra) - there, in that place

• आयुः (āyuḥ) - lifespan, life, duration of life

• भरतर्षभ (bharatarṣabha) - An epithet typically used for a king or hero of the Bharata lineage, like Yudhiṣṭhira. (O best of Bharatas, O chief of Bharatas)

• कालाम्ररसपीताः (kālāmrarasapītāḥ) - having drunk the juice of black mangoes

• ते (te) - they

• नित्यम् (nityam) - always, perpetually, constantly

• संस्थितयौवनाः (saṁsthitayauvanāḥ) - remaining youthful, having fixed youth, perpetually youthful

Words meanings and morphology

दश (daśa) - ten

(indeclinable)

वर्षसहस्राणि (varṣasahasrāṇi) - thousands of years

(noun)

Nominative, neuter, plural of varṣasahasra

varṣasahasra - thousand years

Compound type : tatpurusha (varṣa+sahasra)

• varṣa – year, rain
  noun (neuter)
  Root: vṛṣ (class 1)
• sahasra – thousand
  noun (neuter)
  Root: sah (class 1)

Note: Also could be accusative, but nominative for duration of life is common.

तत्र (tatra) - there, in that place

(indeclinable)

आयुः (āyuḥ) - lifespan, life, duration of life

(noun)

Nominative, neuter, singular of āyus

āyus - life, lifespan, vitality

Root: i (class 2)

भरतर्षभ (bharatarṣabha) - An epithet typically used for a king or hero of the Bharata lineage, like Yudhiṣṭhira. (O best of Bharatas, O chief of Bharatas)

(proper noun)

Vocative, masculine, singular of bharatarṣabha

bharatarṣabha - bull of the Bharatas, best of the Bharatas

Compound type : tatpurusha (bharata+ṛṣabha)

• bharata – descendant of Bharata, one who is supported or maintained, an actor
  proper noun (masculine)
  Root: bhṛ (class 1)
• ṛṣabha – bull, chief, excellent one
  noun (masculine)
  Root: ṛṣ (class 6)

कालाम्ररसपीताः (kālāmrarasapītāḥ) - having drunk the juice of black mangoes

(adjective)

Nominative, masculine, plural of kālāmrarasapītā

kālāmrarasapītā - having drunk the juice of black mangoes

Compound type : bahuvrihi (kālāmrarasa+pīta)

• kālāmrarasa – juice of the black mango
  noun (masculine)
• kālāmra – black mango
  noun (masculine)
• kāla – black, dark, time
  adjective (masculine)
  Root: kal (class 10)
• āmra – mango tree, mango fruit
  noun (masculine)
• rasa – juice, essence, taste, fluid
  noun (masculine)
  Root: ras (class 1)
• pīta – drunk, consumed
  adjective (masculine)
  Past Passive Participle
  from root pā, to drink
  Root: pā (class 1)

Note: Refers to the inhabitants of the region.

ते (te) - they

(pronoun)

Nominative, masculine, plural of tad

tad - that, he, she, it

Note: Can be masculine or feminine plural nominative, here referring to the inhabitants.

नित्यम् (nityam) - always, perpetually, constantly

(indeclinable)

संस्थितयौवनाः (saṁsthitayauvanāḥ) - remaining youthful, having fixed youth, perpetually youthful

(adjective)

Nominative, masculine, plural of saṃsthitayauvanā

saṁsthitayauvanā - having youth established, perpetually youthful

Compound type : bahuvrihi (saṃsthita+yauvana)

• saṃsthita – established, fixed, remaining, existing
  adjective (masculine)
  Past Passive Participle
  from root sthā, to stand, with prefix sam
  Prefix: sam
  Root: sthā (class 1)
• yauvana – youth, state of being young
  noun (neuter)
  Root: yu (class 2)

Note: Refers to the inhabitants, agreeing in gender and number.