When should you use a hyphen in compound words?

A hyphen should be used in compound words in the following situations:

1. To join two or more words that together form a single adjective before a noun. For example, "well-known author" or "high-quality product."

2. To avoid confusion or ambiguity. Hyphens can be used to clarify the meaning of a word or phrase. For instance, "re-cover" (to cover again) versus "recover" (to regain health).

3. To connect a prefix or suffix to a word. Hyphens are used to attach certain prefixes or suffixes to a base word, such as "pre-approval" or "self-confidence."

4. In certain compound numbers. Hyphens are used in compound numbers from twenty-one to ninety-nine, such as "thirty-five" or "seventy-two."

5. In compound words that serve as nouns or verbs. Hyphens are used in compound words that function as nouns or verbs, such as "mother-in-law" or "break-up."

It is important to note that the use of hyphens in compound words can vary depending on style guides and specific word usage. Therefore, it is advisable to consult a dictionary or style guide for specific cases.