महाभारतः mahābhārataḥ - book-1, chapter-71, verse-18

ब्रह्मचर्यं चरिष्यामि त्वय्यहं परमं गुरौ ।
अनुमन्यस्व मां ब्रह्मन्सहस्रं परिवत्सरान् ॥१८॥

18. brahmacaryaṁ cariṣyāmi tvayyahaṁ paramaṁ gurau ,
anumanyasva māṁ brahmansahasraṁ parivatsarān.

18. brahmacaryam cariṣyāmi tvayi aham paramam gurau
anumanyasva mām brahman sahasram parivatsarān

18. I will observe the highest brahmacharya with you, my supreme guru. O Brahmin, please grant me permission for a thousand years.

Words meanings summery:

• ब्रह्मचर्यम् (brahmacaryam) - the vow of celibacy and student life (brahmacharya (religious student life, celibacy))

• चरिष्यामि (cariṣyāmi) - I will observe (the vow) (I will practice, I will observe, I will wander)

• त्वयि (tvayi) - under your guidance/authority (in you, with you, under you)

• अहम् (aham) - I

• परमम् (paramam) - the highest form of brahmacharya (supreme, highest, excellent)

• गुरौ (gurau) - in you, who are my guru (in the guru, to the teacher)

• अनुमन्यस्व (anumanyasva) - please consent to my request (grant permission, consent, agree)

• माम् (mām) - me

• ब्रह्मन् (brahman) - addressing Śukra, who is a Brāhmaṇa (O Brahmin, O Brāhmaṇa)

• सहस्रम् (sahasram) - a thousand

• परिवत्सरान् (parivatsarān) - years

Words meanings and morphology

ब्रह्मचर्यम् (brahmacaryam) - the vow of celibacy and student life (brahmacharya (religious student life, celibacy))

(noun)

Accusative, neuter, singular of brahmacarya

brahmacarya - religious student life, celibacy, chastity

Compound type : tatpurusha (brahman+carya)

• brahman – sacred knowledge, Veda, spiritual power
  noun (neuter)
  Root: bṛh (class 1)
• carya – to be practiced, conduct
  noun (neuter)
  Gerundive
  from root car with suffix -ya
  Root: car (class 1)

चरिष्यामि (cariṣyāmi) - I will observe (the vow) (I will practice, I will observe, I will wander)

(verb)

1st person , singular, active, future (lṛṭ) of car

Root: car (class 1)

त्वयि (tvayi) - under your guidance/authority (in you, with you, under you)

(pronoun)

Locative, singular of yuṣmad

yuṣmad - you

Note: Refers to Śukra.

अहम् (aham) - I

(pronoun)

Nominative, singular of asmad

asmad - I, we

परमम् (paramam) - the highest form of brahmacharya (supreme, highest, excellent)

(adjective)

Accusative, neuter, singular of parama

parama - supreme, highest, most excellent

superlative form

Note: Agrees with brahmacaryam.

गुरौ (gurau) - in you, who are my guru (in the guru, to the teacher)

(noun)

Locative, masculine, singular of guru

guru - teacher, spiritual guide, heavy, important

Note: Agrees with tvayi.

अनुमन्यस्व (anumanyasva) - please consent to my request (grant permission, consent, agree)

(verb)

2nd person , singular, middle, imperative (loṭ) of man

Prefix: anu

Root: man (class 4)

Note: With upasarga 'anu'.

माम् (mām) - me

(pronoun)

Accusative, singular of asmad

asmad - I, we

ब्रह्मन् (brahman) - addressing Śukra, who is a Brāhmaṇa (O Brahmin, O Brāhmaṇa)

(noun)

Vocative, masculine, singular of brahman

brahman - one who possesses sacred knowledge, a Brāhmaṇa

Note: Refers to Śukra.

सहस्रम् (sahasram) - a thousand

(numeral)

Note: Functions as an adjective here, modifying 'parivatsarān'.

परिवत्सरान् (parivatsarān) - years

(noun)

Accusative, masculine, plural of parivatsara

parivatsara - year

Prefix: pari

Root: vas (class 1)

Note: Duration of time is often expressed in accusative.