महाभारतः mahābhārataḥ - book-7, chapter-157, verse-13

तदैव कृतकार्या हि वयं स्याम कुरूद्वह ।
न रक्षेद्यदि कृष्णस्तं पार्थं कर्णान्महारथात् ॥१३॥

13. tadaiva kṛtakāryā hi vayaṁ syāma kurūdvaha ,
na rakṣedyadi kṛṣṇastaṁ pārthaṁ karṇānmahārathāt.

13. tadā eva kṛtakāryā hi vayam syāma kurūdvaha na
rakṣet yadi kṛṣṇaḥ tam pārtham karṇāt mahārathāt

13. kurūdvaha yadi kṛṣṇaḥ tam pārtham mahārathāt
karṇāt na rakṣet hi tadā eva vayam kṛtakāryā syāma

13. O best of Kurus, we would surely have accomplished our task then, if Kṛṣṇa had not protected Arjuna (pārtha) from Karṇa, the great warrior.

Words meanings summery:

• तदा (tadā) - then, at that time

• एव (eva) - indeed, only, just

• कृतकार्या (kṛtakāryā) - we would have accomplished our task (having accomplished one's purpose, successful)

• हि (hi) - indeed, surely, because

• वयम् (vayam) - we

• स्याम (syāma) - we would be, we might be

• कुरूद्वह (kurūdvaha) - O King Dhṛtarāṣṭra (O best of Kurus, O leader of Kurus)

• न (na) - not

• रक्षेत् (rakṣet) - he would protect, he might protect

• यदि (yadi) - if

• कृष्णः (kṛṣṇaḥ) - Kṛṣṇa

• तम् (tam) - Arjuna (him)

• पार्थम् (pārtham) - Arjuna

• कर्णात् (karṇāt) - from Karṇa

• महारथात् (mahārathāt) - from the great warrior, from the great charioteer

Words meanings and morphology

तदा (tadā) - then, at that time

(indeclinable)

एव (eva) - indeed, only, just

(indeclinable)

कृतकार्या (kṛtakāryā) - we would have accomplished our task (having accomplished one's purpose, successful)

(adjective)

Nominative, plural of kṛtakārya

kṛtakārya - one whose purpose has been achieved, successful

Compound of kṛta (done) and kārya (work/purpose)

Compound type : bahuvrīhi (kṛta+kārya)

• kṛta – done, made, accomplished
  adjective (neuter)
  Past Passive Participle
  From root kṛ (to do) with kta suffix
  Root: kṛ (class 8)
• kārya – work, action, purpose, duty
  noun (neuter)
  Gerundive
  From root kṛ (to do) with ṇyat suffix
  Root: kṛ (class 8)

Note: Agreeing with 'vayam' (we)

हि (hi) - indeed, surely, because

(indeclinable)

वयम् (vayam) - we

(pronoun)

Nominative, plural of asmad

asmad - I, we

स्याम (syāma) - we would be, we might be

(verb)

1st person , plural, active, optative (liṅ) of as

Root: as (class 2)

कुरूद्वह (kurūdvaha) - O King Dhṛtarāṣṭra (O best of Kurus, O leader of Kurus)

(noun)

Vocative, masculine, singular of kurūdvaha

kurūdvaha - leader of the Kurus, best of the Kurus

Compound of Kuru (the clan name) and udvaha (bearer/leader)

Compound type : tatpuruṣa (kuru+udvaha)

• kuru – Kuru (proper name, ancestor of a dynasty)
  proper noun (masculine)
• udvaha – bearer, leader, one who carries
  noun (masculine)
  Agent noun
  From root vah (to carry) with prefix ud
  Prefix: ud
  Root: vah (class 1)

न (na) - not

(indeclinable)

रक्षेत् (rakṣet) - he would protect, he might protect

(verb)

3rd person , singular, active, optative (liṅ) of rakṣ

Root: rakṣ (class 1)

यदि (yadi) - if

(indeclinable)

कृष्णः (kṛṣṇaḥ) - Kṛṣṇa

(proper noun)

Nominative, masculine, singular of kṛṣṇa

kṛṣṇa - Kṛṣṇa (proper name); black, dark

तम् (tam) - Arjuna (him)

(pronoun)

Accusative, masculine, singular of tad

tad - that, he, she, it

पार्थम् (pārtham) - Arjuna

(proper noun)

Accusative, masculine, singular of pārtha

pārtha - Arjuna (son of Pṛthā/Kuntī)

Derived from Pṛthā

कर्णात् (karṇāt) - from Karṇa

(proper noun)

Ablative, masculine, singular of karṇa

karṇa - Karṇa (proper name)

महारथात् (mahārathāt) - from the great warrior, from the great charioteer

(noun)

Ablative, masculine, singular of mahāratha

mahāratha - great warrior, great charioteer

Compound of mahā (great) and ratha (chariot/warrior in a chariot)

Compound type : karmadhāraya (mahā+ratha)

• mahā – great, large, mighty
  adjective
• ratha – chariot; warrior in a chariot
  noun (masculine)

Note: Modifying Karṇa