Greek Grammar

The phrear, phreatos. Delear, deleatos. Hydōr water, hydatos.
Hēpar, hēpatos. The belos missile/dart, beleos. The teichos wall, teicheos. The phōs light, phōtos, phōti. The phōs, O phōs. Dual: phōte, phōtoin, O phōte. Plural: phōta, phōtōn, phōsi, phōta, O phōta. The ous ear, ōtos. The kreas flesh, kreatos.
The gēras old age, gēratos.

Concerning the accusative case.

Note regarding this fifth and perittosyllabic having more syllables in the genitive than in the nominative declension: that nouns ending in -is, -i, or -y, if they are declined with a pure -os, even if they are declined perittosyllabically, nevertheless have the accusative case ending in -n, which is equal-syllabled to the nominative. For example: ophis snake, ophios, ophin. The lexis word/diction, lexeōs, lexin. The botrys cluster of grapes, botryos, botryn. The pitys pine tree, pityos, pityn. Since the use of accusatives in -a has generally fallen out of use, in which there is the Ionic form, as -os pure with a dichronos vowel that can be long or short before the end. And likewise for those that are oxytone acute-accented on the final syllable: for example, the hedys sweet, hedeos, hedyn. The ilys mud, ilyos, ilyn. If they are not declined with a pure -os, but with a consonant, if they are oxytone...