Template:el-nN-ος-οτα-1
The inflection-table template for Greek nouns declining like γεγονός (gegonós). Other examples may be found in the Category:Greek nouns declining like 'γεγονός'.
The syntax {{el-nN-ος-οτα-1|γεγον}}
produces the table:
Declension of el-nN-ος-οτα-1
A full list of other declension-table templates with a brief indication of use can be found at Wiktionary:Greek noun inflection-table templates.