What are some nouns that change when they become plural?

Here are some nouns that change when they become plural, categorized by their pluralization rules:

Regular Plurals (add -s or -es):

* Nouns ending in most consonants: book -> books, cat -> cats, flower -> flowers

* Nouns ending in -s, -x, -ch, -sh: bus -> buses, box -> boxes, church -> churches, dish -> dishes

* Nouns ending in -y preceded by a consonant: baby -> babies, story -> stories

* Nouns ending in -o preceded by a consonant: hero -> heroes, potato -> potatoes

* Some nouns ending in -o preceded by a vowel: radio -> radios, studio -> studios

Irregular Plurals:

* Nouns with unique plural forms: man -> men, woman -> women, child -> children, tooth -> teeth, foot -> feet

* Nouns that remain the same in singular and plural: sheep -> sheep, deer -> deer, fish -> fish (sometimes fish)

Nouns with Other Pluralization Rules:

* Nouns ending in -f or -fe: leaf -> leaves, wife -> wives

* Nouns ending in -us: cactus -> cacti, alumnus -> alumni

* Nouns ending in -is: analysis -> analyses, crisis -> crises

* Compound Nouns: mother-in-law -> mothers-in-law, attorney general -> attorneys general

Remember: These are just some common examples. The English language is full of exceptions, so it's always best to consult a dictionary when you're unsure!