Final answer:
Compound modifiers that are often hyphenated represent a single noun and help clarify their function as a unified descriptor before a noun, such as 'well-known author' and 'chocolate-covered peanuts'. They are usually not hyphenated when following the noun they describe.
Step-by-step explanation:
Compounds that are often hyphenated and represent a single noun are known as compound modifiers. These are created when two or more words are joined together to uniquely describe a noun. When used before a noun, they are hyphenated to clarify that they function as a single modifier. For example, 'well-known' in 'well-known author' is a compound modifier that indicates the author is widely recognized. Similarly, 'chocolate-covered' in 'chocolate-covered peanuts' describes peanuts that have been covered in chocolate. Hyphens help avoid confusion, ensuring that each word doesn't modify the noun separately.
However, it's important to note that compound modifiers are usually not hyphenated when they follow the noun they modify. Additionally, certain compound words, like 'blackbird' and 'dogcatcher', don't require hyphens because they are established as single nouns over time. Knowing when to use hyphens with modifiers helps in structuring sentences correctly and enhances the clarity of written communication.