def singular_rules
[
[/(matr)ices$/i, '\1ix'],
[/(vert)ices$/i, '\1ex'],
[/^(ox)en/i, '\1'],
[/(alias)es$/i, '\1'],
[/([octop|vir])i$/i, '\1us'],
[/(cris|ax|test)es$/i, '\1is'],
[/(shoe)s$/i, '\1'],
[/(o)es$/i, '\1'],
[/(bus)es$/i, '\1'],
[/([m|l])ice$/i, '\1ouse'],
[/(x|ch|ss|sh)es$/i, '\1'],
[/(m)ovies$/i, '\1\2ovie'],
[/(s)eries$/i, '\1\2eries'],
[/([^aeiouy]|qu)ies$/i, '\1y'],
[/([lr])ves$/i, '\1f'],
[/(tive)s$/i, '\1'],
[/(hive)s$/i, '\1'],
[/([^f])ves$/i, '\1fe'],
[/(^analy)ses$/i, '\1sis'],
[/((a)naly|(b)a|(d)iagno|(p)arenthe|(p)rogno|(s)ynop|(t)he)ses$/i, '\1\2sis'],
[/([ti])a$/i, '\1um'],
[/(p)eople$/i, '\1\2erson'],
[/(m)en$/i, '\1an'],
[/(s)tatus$/i, '\1\2tatus'],
[/(c)hildren$/i, '\1\2hild'],
[/(n)ews$/i, '\1\2ews'],
[/s$/i, '']
]
end