1) singular noun plus s: student, apple, schoolbag, tree, book, brother. 2) nouns ending in s, x, sh, ch and es: glasses, boxes, brushes and matches. 3) Nouns ending in consonants and Y are changed from Y to I plus es: city, baby, enemy. ? 4) Most nouns ending in F or fe change F into V plus es: wife, knife. But some words just add S: roof, evidence, chief. ? 5) For nouns ending in O, some add ES: black, hero, tomato and potato. Others add s: radio, zoo, piano, photos. 6) Irregular nouns: foot → foot, goose → goose, tooth → tooth, Child → Children, Man → Me N, Woman, sheep, deer → deer, Mouse→Mouse 7) Some foreign words become plural: datum→data, medium→media, bacteria, courses → (? Hmm/? on→a)？ Analysis → analysis, foundation → foundation, crisis → crisis, diagnosis → diagnosis. (? Yes →es)? 8) Compound nouns become plural: compound nouns ending in uncountable nouns have no plural form, such as homework. Compound nouns prefixed with man or woman become plural, and both nouns become plural, such as: manservant→menservans, female student. Other compound nouns become plural: grown? Grow up → grow up? Ups, brother? Are you online? Law → brother? Are you online? Law, position? by→stands？ By. ? 9) when compound adjectives are used as attributes, the nouns in them remain singular: a six? Year? Old boys, a two? A hundred? English nouns can be divided into countable nouns and uncountable nouns. Countable nouns can be in singular and plural forms. One person uses the singular, and two or more people use the plural. The formation of plural nouns can be divided into regular changes and irregular changes.