Context: The Sanskrit grammatical tradition, Vyākaraṇa, one of the six Vedangas, began in the late Vedic period and culminated in the Aṣṭādhyāyī of Pāṇini, which consists of 3990 sutras (ca. fifth century BCE). About a century after Pāṇini (around 400 BCE), Kātyāyana composed Vārtikas on the Pāṇini sũtras. Patanjali, who lived three centuries after Pāṇini, wrote the Mahābhāṣya, the "Great Commentary" on the Aṣṭādhyāyī and Vārtikas. Because of these three ancient Vyākaraṇins (grammarians), this grammar is called Trimuni Vyākarana. To understand the meaning of the sutras, Jayaditya and Vāmana wrote a commentary, the Kāsikā, in 600 CE. Pāṇinian grammar is based on 14 Shiva sutras (aphorisms), where the whole mātrika (alphabet) is abbreviated. This abbreviation is called the Pratyāhara.

Question: What is the Sanskrit grammatical tradition?
Answer: Vyākaraṇa

Question: In what period did Vyakarana begin?
Answer: late Vedic

Question: How many sutras are in the Astadhyayi?
Answer: 3990 sutras

Question: Who composed Vartikas on the Panini sutras?
Answer: Kātyāyana

Question: What is the abbreviated alphabet called? 
Answer: Pratyāhara

Question: What was composed about a century before Panini?
Answer: Unanswerable

Question: Who lived three centuries before Panini?
Answer: Unanswerable

Question: What did Panini write?
Answer: Unanswerable

Question: What is based on 12 Shiva sutras?
Answer: Unanswerable

Question: What is Pratyahara a partial abbreviation of?
Answer: Unanswerable