b. The prefixion of the negative particle, a or an, does not cause the gerund to take the form in ya: thus, akṛtvā, anīrayitvā (but R. has acintya). Of compounds with other than verbal prefixes, RV. has punardā́ya, karṇagṛ́hya, pādagṛ́hya, hastagṛ́hya, araṁkṛ́tya, akkhalīkṛ́tya, mithaspṛ́dhya; AV. has further namaskṛ́tya.
991. The suffix त्वा tvā has the accent. It is usually added directly to the root, but often also with interposition of the auxiliary vowel इ i — with regard to which, as well as to the form of the root before it, the formation nearly agrees with that of the participle in त ta (952 ff.).
a. Examples of the general accordance of passive participle, infinitive, and gerund in regard to the use of i were given above, 968 a; further specifications are called for, as follows:
b. The quotable roots in variable ṛ (242) change it to īr: thus, tīrtvā́, stīrtvā́ (also stṛtvā́); and car makes also cīrtvā (like cīrṇa); — roots in ā show in general the same weakening as in the participle; but from dhā put is quotable only dhitvā́, from mā measure mitvā́ and mītvā, from dā give only dattvā́, from chā chāyitvā; — of roots in am, kram and bhram and yam make forms both with and without i (as in the infinitive), but ram has ratvā́ and raṁtvā, and dam and vam make damitvā and vamitvā.
c. The auxiliary vowel is taken by roots gras, muṣ, çap, and çās (çāsitvā) (whose participles have both forms); also by cāy, nṛt (nartitvā), lag, and svaj (against analogy of pple); and çuc makes çocitvā. On the other hand, from ruj (rugṇa) and vraçc (vṛkṇa) come ruktvā́ and vṛṣṭvā́. And both forms are made (as also in infinitive or participle) from car, vas dwell (uṣṭvā, uṣitvā́), nī (nītvā́, nayitvā), and mṛj (mṛṣṭvā́, mārjitvā).
d. While the formation is in general one requiring, like the passive participle (e. g. uptvā, like uptá; uditvā́, like uditá), a weak or weakened root, there are some cases in which it is made from a strong or strengthened root-form. Thus (besides the instances already given: chāyitvā, raṁtvā, çāsitvā, cāyitvā, çocitvā, nayitvā, mārjitvā), we find charditvā (Āpast.), daṅṣṭvā, and spharitvā, and, from a number of roots, a second strong form beside the more regular weak one: namely, an̄ktvā, bhan̄ktvā, bhun̄ktvā, syanttvā (beside aktvā́ etc.); cayitvā, smayitvā, smaritvā (beside citvā́ etc.); roditvā (beside ruditvā), and siñcitvā (beside siktvā). The last shows the influence of the present-stem; as do also mārjitvā (above) and jighritvā (√ghrā). The form ṣṭhutvā (Āpast.) is doubtless a false reading, for ṣṭhyūtvā.
992. The suffix य ya is added directly to the root, which is accented, but has its weak form. A root ending
