अथ प्रथमाध्यायस्य प्रथमः पादः (1.1)

वृद्धिरादैच्
ā, ai, and au are called vṛddhi.
अदेङ्गुणः
a, e, and o are called guṇa.
इको गुणवृद्धी
The ik vowels become guṇa and vṛddhi,
1. न धातुलोप आर्धधातुके
  except in these cases: when they're in front of an ārdhadhātuka suffix that causes part of a verb root to be deleted;
2. क्ङिति च
  when they're in front of kit or ṅit affixes;
3. दीधीवेवीटां च
  and when they're in dīdhī, vevī, or the iṭ affix.
हलोऽनन्तराः संयोगः
Adjacent consonants are together called saṃyoga ["conjunct"].
मुखनासिकावचनोऽनुनासिकः
Sounds made with both the nose and the mouth are called anunāsika ["nasalized"].
तुल्यास्यप्रयत्नं सवर्णम्
Sounds with the same point of articulation [lips, teeth, ...] and manner of articulation [full contact, no contact, ...] are called savarṇa ["homogeneous"],
1. नाज्झलौ
  but vowels and consonants are not homogeneous to each other.
ईदूदेद्द्विवचनं प्रगृह्यम्
These sounds are called pragṛhya: ī, ū, and e when at the end of a word in the dual [as opposed to the singular or plural];
1. अदसो मात्
  the same sounds after the m of adas;
2. शे
  śe [a Vedic case affix; ś is indicatory, and the real ending is e];
3. निपात एकाजनाङ्
  particles that are just a vowel, except for āṅ;
4. ओत्
  and particles ending in o.
5. सम्बुद्धौ शाकल्यस्येतावनार्षे
  According to Śākalya, the final o of the vocative case is pragṛhya. And, the following things occur in front of iti in non-Vedic literature: the final o of the vocative case is pragṛhya;
  1. उञः
    and a nasal ū replaces uñ.
  2. ऊँ
    (see above.)
6. ईदूतौ च सप्तम्यर्थे
  Finally, ī and ū are pragṛhya when ending a word in the locative case [see SCV for details on arthe].
दाधा घ्वदाप्
Verbs with the form of dā and dhā are called ghu, but verbs with the form of dā and indicatory p are not called ghu.
आद्यन्तवदेकस्मिन्
A single letter is treated like both an initial letter and a final letter.
तरप्तमपौ घः
tarap [tara] and tamap [tama] are called gha.
बहुगणवतुडति संख्या
bahu, gaṇa, words marked with vatu, and words marked with ḍati are all called saṃkhyā ["numerals"]
1. ष्णान्ता षट्
  Those ending in ṣ or n are called ṣaṭ,
  1. डति च
    are are those marked with ḍati.
क्तक्तवतू निष्ठा
kta and ktavatu are called niṣṭhā.
सर्वादीनि सर्वनामानि
The words in the list starting with sarva are called sarvanāma ["pronouns"; SCV for list];
1. विभाषा दिक्समासे बहुव्रीहौ
  they are optionally sarvanāma when in a bahuvrīhi compound signifying a direction,
  1. न बहुव्रीहौ
    but not in any other bahuvrīhi compounds,
  2. तृतीयासमासे
    nor in instrumental tatpuruṣa compounds,
  3. द्वन्द्वे च
    nor in dvandva compounds.
2. विभाषा जसि
  In the nominative plural, these words are optionally sarvanāma: dvandva compounds;
  1. प्रथमचरमतयाल्पार्धकतिपयनेमाश्च
    prathama, carama, alpa, ardha, katipaya, nema, and words ending in taya;
  2. पूर्वपरावरदक्षिणोत्तरापराधराणि व्यवस्थायामसंज्ञायाम्
    pūrva, para, avara, dakṣina, uttara, apara, and adhara when they denote some position in space, but not when they mean anything else;
  3. स्वमज्ञातिधनाख्यायाम्
    sva when it means neither "kinsman" nor "property";
  4. अन्तरं बहिर्योगोपसंव्यानयोः
    and antara when meaning "outer" or "undergarment."
स्वरादिनिपातमव्ययम्
The words in the list starting with svar are called avyaya ["indeclinables"; SCV for list], as are the following:
1. तद्धितश्चासर्वविभक्तिः
  words that end in taddhita affixes and are not declined in all cases;
2. कृन्मेजन्तः
  words that end in kṛt affixes and end in m, e, ai, o, or au;
3. क्त्वातोसुन्कसुनः
  words ending in ktvā, tosun, or kasun;
4. अव्ययीभावश्च
  and the avyayībhāva compound.
शि सर्वनामस्थानम्
The affix śi is called sarvanāmasthāna,
1. सुडनपुंसकस्य
  as are the first five noun affixes [suṭ].
न वेति विभाषा
The word vibhāṣā means "preferably not."
इग्यणः सम्प्रसारणम्
The ik vowels that replace yaṇ are called saṃprasāraṇa
आद्यन्तौ टकितौ
When replacing a term, affixes with indicatory k come after the term and affixes with indicatory ṭ come before it.
मिदचोऽन्त्यात्परः
Affixes with indicatory m come after the last vowel in a word.
एच इग्घ्रस्वादेशे
When a vowel must become short, ec becomes ik [e and ai become i, and o and au become u].
षष्ठी स्थानेयोगा
If a case 6 word is used in this work, the word sthāne ("in its place") is implied with it.
स्थानेऽन्तरतमः
When substituting, the most likely substitute is the right one.
उरण् रपरः
When a vowel is substituted for ṛ, the result is followed by r.
अलोऽन्त्यस्य
When substituting, the last letter of a term [the one in the genitive case] is replaced;
1. ङिच्च
  this rule applies when ṅit affixes are substituted, too.
2. आदेः परस्य
  But if the substitution occurs in a term based on what it follows, then the first letter is replaced instead;
3. अनेकाल्शित्सर्वस्य
  and if the substitute consists of more than one letter or has indicatory ś, then the entire term [the one in the genitive case] is replaced.
स्थानिवदादेशोऽनल्विधौ
A substitute is considered sthānivat [something that behaves the same way as what it replaced], unless the rule is based on the individual letters in a word [i.e. based on its spelling];
1. अचः परस्मिन् पूर्वविधौ
  but a substitute is sthānivat if it replaces a vowel due to a rule about something that follows it.
2. न पदान्तद्विर्वचनवरेयलोपस्वरसवर्णानुस्वारदीर्घजश्चर्विधिषु
  A substitute is not sthānivat in rules about the following: the ends of words, the doubling of letters, adding varac to the end of a word, the deletion of y, accent, homogeneous letters [savarṇa], the anusvāra, the lengthening of a vowel, the substitution of jaś [voiced unaspirated consonants], or the substitution of car [unvoiced unaspirated consonants];
  1. द्विर्वचनेऽचि
    but when the substitute is followed by an affix that both causes reduplication and starts with a vowel, the substitute is considered sthānivat during the actual reduplication [but not beyond that].
अदर्शनं लोपः
The word lopa means "disappearance."
1. प्रत्ययस्य लुक्श्लुलुपः
  The terms luk, ślu, and lup can delete an affix.
2. प्रत्ययलोपे प्रत्ययलक्षणम्
  If an affix is deleted, operations are performed as if it were still there,
  1. न लुमताऽङ्गस्य
    unless the affix of an aṅga [noun or verb stem] was deleted by lu [luk, ślu, or lup].
अचोऽन्त्यादि टि
The last part of a word, beginning with its last vowel, is called ṭi.
अलोऽन्त्यात् पूर्व उपधा
In a word, the letter right before the last letter is called upadhā ["penultimate"].
तस्मिन्निति निर्दिष्टे पूर्वस्य
The locative case marks the term that comes after a substitution.
तस्मादित्युत्तरस्य
The ablative case marks the term that comes before a substitution.
स्वं रूपं शब्दस्याशब्दसंज्ञा
In this grammar, a rule applying to a word applies to that word itself [and not to words with similar meanings], unless the word is a definition.
1. अणुदित् सवर्णस्य चाप्रत्ययः
  Vowels, semivowels, and letters with indicatory u: when they are not affixes, these terms refer to both themselves and all of their savarṇa [homogeneous] letters.
  1. तपरस्तत्कालस्य
    But a letter followed by indicatory t refers only to homogeneous letters with the same duration [i.e. a refers to a and ā, but at refers to just a].
2. आदिरन्त्येन सहेता
  A letter followed by an it letter refers to both itself and all intervening letters [interpretation of the pratyāhāra].
3. येन विधिस्तदन्तस्य
  A rule applying to some attribute applies to both the attribute alone and words that end in that attribute.
वृद्धिर्यस्याचामादिस्तद् वृद्धम्
These words are called vṛddha: a word whose first vowel is vṛddhi;
1. त्यदादीनि च
  words in the list starting with tyad [see 1.1.27];
2. एङ् प्राचां देशे
  and words whose first vowel is e or o, if the word refers to an Eastern country.