What are the example of compound words that plural?

You're asking about plural forms of compound words, which can get a bit tricky! Here's a breakdown:

Types of Compound Words and Their Pluralization:

* Closed Compound Words: These words are written as one word (e.g., "toothbrush," "notebook"). Usually, you simply add -s to the end: toothbrushes, notebooks.

* Hyphenated Compound Words: These words are joined by a hyphen (e.g., "mother-in-law," "merry-go-round"). Pluralization is tricky, and there are two main ways:

* Add -s to the end: mothers-in-law, merry-go-rounds (most common)

* Add -s to the most important word: mother-in-laws, merry-go-rounds (less common, but sometimes used, especially if the word is more noun-like)

* Open Compound Words: These words are written as separate words (e.g., "high school," "full moon"). You pluralize the most important word: high schools, full moons.

Examples:

* Closed Compound Words:

* toothbrushes

* notebooks

* boyfriends

* breakdowns

* Hyphenated Compound Words:

* mothers-in-law

* merry-go-rounds

* passers-by

* well-wishers

* Open Compound Words:

* high schools

* full moons

* post offices

* dining rooms

Important Notes:

* Context matters: Sometimes the best plural form depends on the meaning and how the word is used in a sentence.

* Check a dictionary: If you're unsure, always consult a dictionary for the most accurate pluralization of a compound word.

Let me know if you have any more questions about compound words!