English Pluralization Rules

• English plurals denote more than one of a noun
• Most nouns form plurals by adding "-s" or "-es" to the singular form
• However, English has irregular plurals and words borrowed from other languages that retain their original plural forms

Regular Plurals

• Regular plurals are typically formed by adding "-s" to the end of the singular noun
• Examples include "cat" becoming "cats," "dog" becoming "dogs," and "house" becoming "houses"
• For nouns ending in "-s," "-ss," "-sh," "-ch," "-x," or "-z," add "-es" to form the plural
• Examples include "bus" becoming "buses," "dress" becoming "dresses," "dish" becoming "dishes," "watch" becoming "watches," "box" becoming "boxes," and "quiz" becoming "quizzes"
• For nouns ending in a consonant followed by "y," change the "y" to "i" and add "-es"
• Examples include "baby" becoming "babies," "city" becoming "cities," and "story" becoming "stories"
• Some nouns ending in "-o" also form plurals by adding "-es"
• Examples include "potato" becoming "potatoes," "tomato" becoming "tomatoes," and "hero" becoming "heroes"
• However, many nouns ending in "-o" take only "-s"
• Examples include "photo" becoming "photos," "piano" becoming "pianos," and "video" becoming "videos"

Irregular Plurals

• Irregular plurals do not follow the standard rules of adding "-s" or "-es"
• Some nouns have completely different plural forms
• Examples include "man" becoming "men," "woman" becoming "women," "child" becoming "children," "foot" becoming "feet," "tooth" becoming "teeth," "goose" becoming "geese," and "mouse" becoming "mice"
• Some nouns have the same form in both singular and plural
• Examples include "sheep," "deer," "fish," "species," "series," and "aircraft"
• Nouns ending in "-f" or "-fe" often change the "f" to "v" and add "-es"
• Examples include "leaf" becoming "leaves," "wife" becoming "wives," "knife" becoming "knives," "life" becoming "lives," and "wolf" becoming "wolves"
• However, some nouns ending in "-f" or "-fe" simply add "-s"
• Examples include "chief" becoming "chiefs," "roof" becoming "roofs," "cliff" becoming "cliffs," "safe" becoming "safes," and "grief" becoming "griefs"
• Some nouns have two acceptable plural forms, one regular and one irregular
• Examples include "scarf" becoming "scarfs" or "scarves," "dwarf" becoming "dwarfs" or "dwarves," and "hoof" becoming "hoofs" or "hooves"

Foreign Plurals

• Some English words are borrowed from other languages and retain their original plural forms
• These words often come from Latin, Greek, or French
• Latin plurals ending in "-a"
• Singular forms ending in "-um" often change to "-a" in the plural
• Examples include "curriculum" becoming "curricula," "datum" becoming "data," "medium" becoming "media," and "memorandum" becoming "memoranda"
• Latin plurals ending in "-i"
• Singular forms ending in "-us" often change to "-i" in the plural
• Examples include "alumnus" becoming "alumni," "cactus" becoming "cacti," "focus" becoming "foci," "radius" becoming "radii," and "nucleus" becoming "nuclei"
• Greek plurals ending in "-es"
• Singular forms ending in "-is" often change to "-es" in the plural
• Examples include "analysis" becoming "analyses," "axis" becoming "axes," "basis" becoming "bases," "crisis" becoming "crises," "hypothesis" becoming "hypotheses," and "thesis" becoming "theses"
• Some borrowed words have both a foreign plural and an anglicized plural form
• "Index" can be either "indices" (foreign) or "indexes" (anglicized)
• "Appendix" can be either "appendices" (foreign) or "appendixes" (anglicized)
• "Formula" can be either "formulae" (foreign) or "formulas" (anglicized)
• The choice between the foreign plural and the anglicized plural often depends on context, formality, and usage
• In scientific and academic contexts the foreign plural is more common
• In general and informal contexts the anglicized plural is more common
• Some words borrowed from French do not change in the plural, or follow French pluralization rules
• Examples may include "tableau" becoming "tableaux", or remaining "tableau"