Which sentence has the correct hyphen usage? 

1. She is a well known artist
2. She is a well-known artist
3. She is a wellknown artist
4. She is a well,known artist

Compound adjectives before nouns require hyphens (AP Style). “Well-known” modifies “artist,” so hyphenation prevents misreading. Exceptions: adverbs ending in -ly (e.g., “highly paid actor”). Post-noun positions often drop hyphens: “The artist is well known.”