Small marks change meaning. When two or more words work together to describe a noun that follows, English usually links them with a hyphen: a push-up bra, a part-time job, a four-wheel-drive car. Missing hyphens can make writing look careless or create ambiguity.
Quick answer
Hyphenate compound adjectives that come before a noun; leave them open after a linking verb. Example: She wore a push-up bra. The bra is push up (or better: the bra has push-up padding).
- Before a noun: hyphenate (a five-year plan).
- After a linking verb: don't hyphenate (the plan lasted five years).
- If the first word ends in -ly: no hyphen (a highly skilled candidate).
Hyphenation rules at a glance
When two or more words act as a single unit that modifies a noun, hyphenate them to show they belong together. That prevents misreading-e.g., "small business owner" vs. "small-business owner."
- Attributive position (before the noun): hyphenate many compounds (a user-friendly app).
- Predicative position (after verbs like be, feel, become): usually leave open (the app is user friendly).
- Adverbs ending in -ly + adjective: do not hyphenate (a highly regarded study).
- Numbers and ages: hyphenate when they modify a noun before it (a two-week course).
- If a phrase is unclear or clunky, rewrite (a penalty-free fix).
- Wrong: She wore a pushup bra.
- Right: She wore a push-up bra.
- Wrong: He is a part time employee.
- Right: He is a part-time employee.
Attributive vs. predicative - where the hyphen matters
Place matters. If the compound directly precedes the noun it modifies (attributive), hyphenate. If the same words follow a linking verb (predicative), leave them open.
- Attributive: a long-term strategy (hyphen).
- Predicative: the strategy is long term (no hyphen).
- Quick test: move the phrase after the noun-if the hyphen disappears naturally, you likely need it before the noun.
- Wrong: The policy is short-term.
- Right: The policy is short term. (But: a short-term policy.)
- Wrong: She is a two year veteran.
- Right: She is a two-year veteran.
Spacing, closed compounds and when words fuse
Compounds can move from hyphenated to closed over time (e-mail → email, make-up → makeup). Check a current dictionary or a house style. If unsure, hyphenate until the closed form is established.
Open compounds-two separate words-stay open when each word separately modifies the noun: coffee table leg (no hyphen).
- If dictionaries list the combined form as one word, use the closed form.
- When uncertain, hyphenate before a noun to reduce ambiguity.
- Brands and product names may ignore these rules-follow the brand's form.
- Wrong: He drives a four wheel drive car.
- Right: He drives a four-wheel-drive car.
- Note: Over time, some compounds (website, email) shed their hyphens; check usage.
Examples you can copy (work, school, casual)
Swap in your own nouns and numbers and use the same hyphenation pattern. These templates work across tones-only the wording changes.
- Work - Wrong: The product needs a user friendly interface.
- Work - Right: The product needs a user-friendly interface.
- Work - Wrong: Please prepare a five year forecast.
- Work - Right: Please prepare a five-year forecast.
- Work - Wrong: We expect a data driven decision.
- Work - Right: We expect a data-driven decision.
- School - Wrong: She submitted a term long project.
- School - Right: She submitted a term-long project.
- School - Wrong: The two credit course is difficult.
- School - Right: The two-credit course is difficult.
- School - Wrong: A year long study showed mixed results.
- School - Right: A year-long study showed mixed results.
- Casual - Wrong: She packed her go to outfit.
- Casual - Right: She packed her go-to outfit.
- Casual - Wrong: He bought a sun dried tomato jar.
- Casual - Right: He bought a sun-dried tomato jar.
- Casual - Wrong: She carries a makeup bag.
- Casual - Right: She carries a make-up bag. (Note: makeup is now often closed-check a current dictionary.)
Try your own sentence
Context clarifies. Paste your complete sentence into a checker or read it aloud: if the hyphen improves immediate understanding, use it. If it sounds crowded, rewrite.
Rewrite options when hyphens look clunky
A rewrite often reads cleaner than a string of hyphens. Use prepositional phrases, relative clauses, or simpler phrasing to remove awkward compounds.
- Prepositional: She wore a push-up bra → She wore a bra with push-up padding.
- Relative clause: a decision-based policy → a policy that is based on decisions.
- Plain wording: a user-friendly interface → an interface that's easy to use.
- Rewrite: She wore a push-up bra → She wore a bra with push-up padding.
- Rewrite: a five-year forecast → a forecast covering five years.
- Rewrite: a user-friendly interface → an interface that's easy to use.
How to fix your sentence - step by step
- Identify whether the words form a single idea before a noun. If they do, hyphenate.
- If the first word ends in -ly, do not hyphenate.
- If the phrase follows a linking verb, leave it open or rewrite for clarity.
- If you still hesitate, rewrite the phrase using a preposition or clause.
Quick patterns: numbers/ages + unit = hyphen (a 10-year plan). Adjective + noun forming a standard unit often hyphenated (a high-quality product). When in doubt, rewrite or consult a dictionary/style guide.
- Checklist: attributive? → hyphenate. Predicative? → don't hyphenate.
- If unsure, rewrite to avoid awkward compounds.
- Usage: I need a part time assistant. → I need a part-time assistant.
- Usage: The assistant is part time. → Predicative: The assistant is part time.
- Usage: She bought a leather lined jacket. → leather-lined jacket.
Real usage and tone - pick the right style
Different audiences move at different speeds. News and tech outlets often adopt closed forms earlier; academic and legal writing favors conservative forms. Follow the house style when one exists and be consistent throughout a document.
- For resumes and proposals, choose hyphenation that aids quick scanning (a results-driven leader).
- For casual messages, readers tolerate looser forms; for formal writing, be precise and consistent.
- Usage: On a resume: results-driven manager. In a text message, results driven is usually fine.
- Usage: Style guides like APA recommend hyphenating compound adjectives before a noun (two-way communication).
Similar mistakes to watch for
Common errors: hyphenating adverbs ending in -ly, skipping hyphens with numbers and units, and confusing compound nouns with compound adjectives.
- Don't hyphenate adverbs ending in -ly + adjective: highly skilled (not highly-skilled).
- Hyphenate number + unit when used before a noun: a ten-pound baby.
- Compound nouns are not always hyphenated: coffee table (not coffee-table table).
- Use an en dash, not a hyphen, for ranges (2019-2020).
- Wrong: She is a highly-skilled programmer.
- Right: She is a highly skilled programmer.
- Wrong: A ten pound baby arrived yesterday.
- Right: A ten-pound baby arrived yesterday.
FAQ
Do I hyphenate push up when it modifies a noun?
Yes-when "push-up" comes directly before a noun as a single modifier, hyphenate: she wore a push-up bra. After a linking verb, prefer a rewrite: the bra has push-up padding.
Is it part time or part-time in a sentence?
Use part-time before a noun (a part-time job). After a linking verb, leave it open: his job is part time.
Should numbers be hyphenated in modifiers (five year plan)?
Yes-hyphenate number + unit when it modifies a noun before it: a five-year plan. If the phrase follows a verb, write it open: the plan lasted five years.
When do I close compounds instead of hyphenating?
Many compounds become closed over time. Check a current dictionary; if the closed form is established, use it. If uncertain, hyphenate until usage settles.
How do I check a sentence quickly for the right hyphenation?
Ask: is the compound directly before a noun and acting as a single modifier? If yes, hyphenate. If it follows a linking verb, don't. When in doubt, rewrite or run the full sentence through a grammar checker.
Want to check your sentence quickly?
Paste the complete sentence into a grammar checker to see hyphen suggestions and rewrites. Automated tools catch many patterns, but use the short checklist above to choose the clearest final form.
Try checking a sentence with Linguix or your preferred editor to get suggested hyphens and alternate phrasings, then apply the simple tests in this page.