Universal sentence-level principles that apply to every customer-facing format. Pairs with copywriting-mastery (practitioner-specific moves) and design-thinking-for-content (structure).
Source synthesis: Harry Dry (Marketing Examples), Strunk + White, William Zinsser, George Saunders, Verlyn Klinkenborg. Operator cards for these voices are pending future ingest from primary sources.
Three quality tests
Apply to every sentence.
- Visualization test (Harry Dry). If the reader cannot picture it, they will not remember it. Zoom in until you reach something concrete. "Unlock productivity" → "Reps make 50 calls instead of 15."
- Falsifiability test. If a claim cannot be proven true or false, it has no persuasive power. "Unlock your brain's superpowers" → "One capsule equals six hours of focus." Every benefit must be testable.
- Uniqueness test. "Never write an ad a competitor can sign." If a competitor could lift the sentence for their product, it has no differentiation value. Cut it or rewrite with specific proof.
Sentence-level craft
Economy
- Target: under 25 words per sentence.
- Cut filler: "in order to" → "to"; "at this point in time" → "now"; "due to the fact that" → "because."
- Cut qualifiers: really, very, quite, somewhat, actually, basically.
- One idea per sentence.
Active voice
Default to active. Subject does the verb. Ctrl-F "by" to find passive constructions and rewrite. Passive is fine when the actor is unknown or unimportant.
Concrete > abstract
Specific nouns. Specific numbers. Named entities. Replace categorical words with the closest concrete instance.
Verbs over modifiers
Strong verbs carry sentences. "Walk slowly" → "amble." "Look quickly" → "glance." Adverbs are usually evidence the verb is weak.
Rhythm
Vary sentence length. Short. Then medium length to give a thought room. Then longer constructions that expand the breath. The pattern is what makes prose readable.
Six formulas
- PAS: Pain, Agitate, Solution. Short copy.
- AIDA: Attention, Interest, Desire, Action. Long copy.
- 4Ps: Picture, Promise, Prove, Push.
- BAB: Before, After, Bridge.
- FAB: Features, Advantages, Benefits.
- 3W: What it is, Why it matters, So what outcome.
Empty-modifier blocklist
Delete on sight: powerful, robust, seamless, cutting-edge, innovative, comprehensive, world-class, best-in-class, next-generation, revolutionary, holistic, leverage (as verb), unlock (as verb), transform.
Voice rules
- "You" not "we", buyer as agent.
- Conversational, write like you talk to a smart friend.
- Specific, names, numbers, places.
- Honest, concede limits before they're asked.
- Cut throat-clearing openers ("In today's fast-paced world...").
CTA craft
- One primary CTA per section.
- Verb that matches what happens on click. "Book a demo" if it books a demo.
- Repeat the CTA throughout the page.
- Risk-reversal copy near the CTA reduces friction.
Quality gates
- Every sentence passes visualization, falsifiability, and uniqueness tests.
- No empty modifiers from the blocklist.
- Active voice throughout.
- Single CTA per section, or clear primary/secondary hierarchy.
Common failure modes
- Feature dumping without benefit translation.
- "We" language instead of "you" language.
- Clever over clear.
- Vague claims that could apply to any product.
- Multiple competing CTAs with no hierarchy.
- Addressing multiple audiences in one piece.
- Rounding numbers ("over 60%") instead of citing the exact figure.
- Mixing voice across sections (formal hero, casual body).