A large majority of nouns in the English Language are pluralized by adding an "s" or "es" to the end of the word and They are called regular plurals. Nouns that don't follow the above rule are called irregular plurals.
Singular Plurals
Person People
Foot Feet
Tooth Teeth
Child Children
Mouse Mice
Sheep Sheep
Fish Fish
Leaf Leaves
Goose Geese
Woman Women
Man Men
Aircraft Aircraft
Index Indices
Syllabus Syllabi
Axis Axes
Criterion Criteria
Medium Media
Curriculum Curricula
Formula Formulae / Formulas
Fungus Fungi
Phenomenon Phenomena
Bacterium Bacteria
Nucleus Nuclei
Analysis Analyses
Appendix Appendices
Vertebra Vertebrae
