The traditional Tamil grammar Tolkappiyam describes phonetic, phonological and orthographic aspects of the Old Tamil sound system without distinguishing these three aspects as is done in modern linguistics. The phonemic inventory of the language consists of ten vowels and 17 consonants. Comparative Dravidian phonology indicates the presence of distinct dental, alveolar and retroflex series in the proto-language. Old Tamil morphology is on the whole agglutinating, with a one-to-one correspondence between morpheme and morph. Old Tamil has two major parts of speech noun and verb. Most lexical stems belong to one of these two classes; some stems have a double categorial status such as col which can be the verb stem ‘say’ or the noun stem ‘word’. As K. Ramasamy shows, the correlative strategy is used where a variety of constraints prohibit use of the adnominal strategy. It is an integral part of Tamil syntax.