Some modes , called ómatehtar -LRB- or vowel tehtar -RRB- modes , are abugidas representing vowels with diacritics called tehtar -LRB- `` signs '' ; corresponding singular : tehta , `` sign '' -RRB- , while other modes , called full writing modes , represent vowels by full letters .

These vowel signs are called tehtar -LRB- `` signs '' ; singular : tehta , `` sign '' -RRB- .
