ktānta-rūpa (the form ending in the suffix -kta क्त)

 The ktānta-rūpa (the form ending in the suffix -kta क्त) is the primary way to express a completed action in the karmaṇi prayoga (कर्मणि प्रयोग - passive voice) and the bhāve prayoga (भावे प्रयोग - impersonal voice). This is its main function.

Let's delve into this. The suffix -kta (क्त) is one of two suffixes that Pāṇini calls niṣṭhā (निष्ठा), which denotes completion (past tense). The sūtra is:

क्तक्तवतू निष्ठा (ktaktavatū niṣṭhā) - Aṣṭādhyāyī 1.1.26

This establishes that -kta (क्त) and -ktavatu (क्तवतु) are the past participle suffixes. The key is knowing which one to use in which voice (prayoga).

1. Kta in Karmaṇi Prayoga (कर्मणि प्रयोगे क्त-प्रत्ययः)

In the passive voice, the kta-participle is used to describe a completed action that was performed on the object.

Grammatical Structure:

• The object (कर्मन्) of the action is in the nominative case (प्रथमा विभक्ति - prathamā vibhakti).
• The agent (कर्तृ) is in the instrumental case (तृतीया विभक्ति - tṛtīyā vibhakti).
• The ktānta-rūpa acts like an adjective and agrees with the object in gender, number, and case (लिङ्ग-वचन-विभक्ति).

Example:

• Active Past Tense (Kartari Prayoga): रामः ग्रन्थम् अपठत्। (rāmaḥ grantham apaṭhat.) - "Rama read the book."
• Passive with -kta (Karmaṇi Prayoga): रामेण ग्रन्थः पठितः। (rāmeṇa granthaḥ paṭhitaḥ.) - "The book was read by Rama."

Let's analyze this:

• रामेण (rāmeṇa) - The agent (Rama) is in the instrumental case.
• ग्रन्थः (granthaḥ) - The object (book) is in the nominative case, masculine, singular.
• पठितः (paṭhitaḥ) - The kta-participle of the root paṭh (पठ् - to read). It agrees with ग्रन्थः and is therefore masculine, singular, nominative.

Another example to show agreement:

• Active: सीता पत्रम् अलिखत्। (sītā patram alikhat.) - "Sita wrote the letter."
• Passive: सीतया पत्रं लिखितम्। (sītayā patraṃ likhitam.) - "The letter was written by Sita."
  • Here, पत्रम् (patram) is neuter singular, so the participle is लिखितम् (likhitam), also neuter singular.

2. Kta in Bhāve Prayoga (भावे प्रयोगे क्त-प्रत्ययः)

In the impersonal voice, used with intransitive verbs (अकर्मक धातु), the kta-participle signifies that the action has happened.

Grammatical Structure:

• There is no object.
• The agent (कर्तृ) is in the instrumental case (तृतीया विभक्ति).
• The ktānta-rūpa is always in the neuter singular nominative form: नपुंसकलिङ्ग-एकवचन-प्रथमाविभक्ति। It does not agree with anything.

Example:

• Active Past Tense (Kartari Prayoga): देवः अहसत्। (devaḥ ahasat.) - "Deva laughed."
• Impersonal with -kta (Bhāve Prayoga): देवेन हसितम्। (devena hasitam.) - Literally, "It was laughed by Deva," meaning "Deva laughed."

Let's analyze this:

• देवेन (devena) - The agent (Deva) is in the instrumental.
• हसितम् (hasitam) - The kta-participle of the root has (हस् - to laugh). It is in the fixed neuter singular form.

Another example:

• Active: बालौ अगच्छताम्। (bālau agacchatām.) - "The two boys went."
• Impersonal: बालाभ्याम् गतम्। (bālābhyām gatam.) - "It was gone by the two boys," meaning "The two boys went."
  • Notice that even though the agent बालाभ्याम् (bālābhyām) is dual, the participle गतम् (gatam) remains neuter singular.
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Summary: Tvānta vs. Ktānta

• त्वान्त (-tvā): Used for a prior action by the same agent. It is an element of the Kartari Prayoga (active voice).
  • रामः स्नात्वा खादति। (rāmaḥ snātvā khādati.) - "Rama, having bathed, eats."
• क्तान्त (-kta): Used for a completed action in the Karmaṇi/Bhāve Prayoga (passive/impersonal voice). It replaces the main finite verb for the past tense.
  • रामेण स्नानान्तरं खादितम्। (rāmeṇa snānāntaraṃ khāditam.) - "After bathing, it was eaten by Rama." (A bit convoluted, but illustrates the point).
  • Better: रामेण भोजनं खादितम्। (rāmeṇa bhojanaṃ khāditam.) - "The food was eaten by Rama."

संक्षेपतः, 'क्त'-प्रत्ययः भूतकालिकः कर्मवाच्यस्य भाववाच्यस्य च कृदन्तः अस्ति। अयं तस्य मुख्यः प्रयोगः। (In short, the -kta suffix is the past participle for the passive and impersonal voices. This is its primary usage.)