பக்கம் எண் :

Derivational Changes193

     Even now, any word or sound can be used as a noun, if it refers to itself.

šu˜, pungency-Root.
šey, deed; šol, word;
aŠi, knowledge.
maŠŠu, to change-Stem.   
} Verbal theme.

(2) Mutation of Radical Consonant of Verbal Themes:
  e.g.vel, to conquer, ven, victory.
   v„˜, to desire, v„–, desire.
   
(3) Lengthening of Radical Vowel of Verbal Themes:
   e.g. u, to eat ; ‡–, eating, food.
     padu, to suffer ; pƒdu, suffering.
   
(4) Reduplication of Radical Consonant of Verbal Themes:
   e.g. ƒdu, to play, dance ; ƒ——u, playing, dancing.
     k‡Šu, to state ; k‡ŠŠu, stating, statement.
   
(5) Hardening of Radical Nasal of Verbal Themes:
  e.g. vaaŒgu, to be used, to be current, to be in     vogue.vaakku, usage.
   
(6) Addition of Suffixes:
  Addition of Suffixes to Verbal Themes or Relative Participles.
   

     Suffixes of verbal nouns are of five classes, viz:, (a) deictic elements, (b) nouns signifying place, (c) names of organs (figuratively used as names of place), (d) nouns signifying measurement or intensity, and (e) nouns signifying quality or nature.

Verbal Nouns (ToiŠpeyar)     

 e.g.  šey (to do)+al=š)eyal, doing, deed
         vƒ (to come)+avu=varavu, coming.
}deictic elements.
     
  ka——u, to tie, to bind, to build, to
construct, to pay (as fees),
ka——u+idam=ka——idam, a site
}