[n.] a letter,including the vowels. In the Thai alphabet,the consonants and vowels are grouped separately.There are nominally 44 consonants, but two are practically obsolete, and six more are never used to begin a word,leaving only 36. There are, however, four ligatures, namely, ฤ and ฤา ,which are entered after ร, and ฦ and ฦา , which have become practically obsoleteThe consonants are divided into three tonal groups, low-tone, medium-tone,and high-tone.In the following list,