Final answer:
In Ancient Greek's third declension, a tau changes to a sigma if it's at the end of a stem or followed by a sigma. Other linguistic rules include alphabetic changes based on stem position and spelling variations for 'k' depending on the preceding vowel length.
Step-by-step explanation:
In the third declension of Ancient Greek, if a tau is at the end of a stem or followed by a sigma, the tau changes to sigma. Nouns in the Greek language have various endings based on gender and declension. For instance, certain masculine nouns end in nu, rho, sigma, psi, or xi, while feminines can end in long vowels such as eta and omega, or a lengthened alpha. Neuter nouns often end in vowels like iota and upsilon, or consonants such as nu and sigma. When dealing with specific changes in letters due to position, another rule comes into play: When the letters ll are at the end of a free stem, an a before them will spell 'o', and when ll is in the middle of a stem, the a before them will spell 'a'. Regarding spelling rules for the letter k, in words where it precedes an le at the end of a word with a heavily stressed vowel before the k, the k is spelt as a 'c' if the vowel is short, and as a 'k' if the vowel is long.