Irregular Plurals | Irregular Plurals Nounn in English Singular Plural Trout Trout Genus Genera Focus Foci Person People Tooth Teeth Curriculum Curricula Mouse Mice Wife Wives Deer Deer Vita Vitae Quiz Quizzes Index Indices Datum Data Aircraft Aircraft Woman Women Leaf Leaves Fish Fish Sheep Sheep Singular Plural Goose Geese Tuna Tuna Ellipsis Ellipses Codex Codies Lavra Lavrae Erratum Errata Oasis Oases Ox Oxen Swine Swine Trout Trout Analysis Analyses Series Series Child Children Foot feet Nebula Nebulae Leaf Leaves Diagnosis Diagnoses Alumna Alumnae Singular Plural Addendum Addenda Aircraft Aircraft Alumna Alumnae Alumnus Alumni Analysis Analyses Antenna Antennae Antithesis