Changing Singular Nouns to PLural Nouns

Compound words written as as single words follow the general rule for forming plurals.

Textbook, textbooks, Englishman, Englishmen.

The plural of nouns ending in y prededed by a vowel add -S.

Donkey, donkeys, alley, alleys, key, keys.

The plural of nouns ending in Y preceded by a consonant change the Y to I.

Baby, babies, army, armies, lady, ladies.

The plural of nouns inding in IS change IS to ES.

Basis, bases, parenthesis, parentheses.

The plural of nouns ending in o preceded by a vowel add -S.

Belief, beliefs, chief, chiefs. Some nouns ending is For FEchange the F to V and add -S or -ES. Knife, knives, half, hlves, thief, thieves.

The plural of nouns ending in S, X, z, CH, or SH, add -ES

Church, churches, box, boxes, glass, glasses.

For words derived from Latin, UM is singular and A is plural.

Datum, data, memorandum, memoranda, curriculum, curricula. Words that end in US change to I. Radius, radii, focus, foci, alumnus, alumni. Words that end in ON change to A. Phenomenom, phenomena, criterion, criteria.

The plural of some nouns is irregular and must be memorized.

Foot, feet, ox, oxen, woman, women, child, children, mouse, mice.

The plural of nouns ending in o preceded by a consonant add -ES.

Hero, heroes, tomato, tomatoes. This rule is not always consistent. You will have to memorize some forms, such as silo, silos.

The regular way to form a plural of a noun is to add an -S.

Lake, lakes, picture, pictures, girl, girls.

Compound words written with hyphens or as separate words make for one modified word plural.

Passer-by, passers-by, mother-in-law, mothers-in-law, suit os armor, suits of armor.