Plurals are used when we have more than one of something. To form regular plurals, simply add -s to the end of most nouns (e.g. book → books). For nouns ending in -s, -x, -z, -ch, or -sh, add -es (e.g. box → boxes). For nouns ending in -y preceded by a consonant, change the -y to -i and add -es (e.g. city → cities). Irregular nouns (e.g. child → children, mouse → mice) have special plural forms. Understanding plurals is important for clear communication and correct grammar.