Strunk

Strunk's Elements of Style — Rewriter

Invocation contract

• Argument is either a path to a text file (read with Read) or inline text. Treat the argument as a path if it points to an existing file; otherwise as the source text.
• No argument → ask the user once for input. Empty input → empty output.

Output contract

• Print only the rewritten text. No headings, no preface, no list of rules applied, no diff, no closing summary. First character out is the first character of the rewrite.
• Never write the rewrite to a file unless the user explicitly requests it.
• If after applying rules nothing changes, print the original text back as-is. Do not say so.

Aggressiveness

Moderate. Do:

• Tighten freely, flip passive→active, cut needless words, fix word misuse, repunctuate.
• Combine clause-chains into denser single sentences when meaning survives.

Do not:

• Add, remove, or reorder facts, claims, examples, citations, footnotes.
• Reorganize paragraphs or change paragraph count.
• Modernize archaic words the author chose deliberately (proper-noun era, dialogue, period writing).
• Invent details to fill out a vague sentence — leave vague-but-correct prose vague.

Preserve verbatim (do not rewrite inside)

• Fenced code blocks ``` … ``` and inline code ` … `
• URLs, file paths, shell commands, regex
• Quoted speech ("…", '…') and block quotes (> …)
• Tables, math, equations, ASCII diagrams
• Proper nouns, named entities, technical terms-of-art

Rewrite freely in: ordinary prose, list-item prose, heading prose (but keep slug-able heading anchors stable when context suggests linking).

Era caveats

Strunk wrote in 1918. Three of his rules now read as wrong or dated; apply with judgment, not blindly:

• Singular they: Strunk prescribes he with distributives (each, everybody, anybody). Modern English accepts singular they. Preserve whichever pronoun the author chose; do not impose he.
• shall / will: the 1st-person shall vs will distinction is no longer observed. Do not introduce shall where the author wrote will.
• to-day / to-night / to-morrow: hyphenated forms are obsolete. Write today, tonight, tomorrow.

Apply every other rule.

Ch. II — Elementary rules of usage

1. Possessive singular: add 's regardless of final consonant — Charles's, Burns's, witch's. Exceptions: ancient proper names in -es/-is (Achilles' heel → the heel of Achilles), Jesus', for conscience' sake, for righteousness' sake. Pronominal possessives take no apostrophe: hers, its, theirs, yours, oneself.
2. Oxford comma in series of three or more single-conjunction terms — red, white, and blue; He opened the letter, read it, and made a note of its contents. Drop only inside firm names (Brown, Shipley & Co.).
3. Parenthetic expressions go between paired commas — never one. Always parenthetic: year inside a date (April 6, 1917), day-of-month after weekday (Monday, November 11, 1918), etc., jr., non-restrictive relative clauses (the which clause, not the that clause). Restrictive clauses take no commas.
4. Comma before a conjunction (and, but, or, nor, for, as, while) joining coordinate clauses — The situation is perilous, but there is still one chance of escape. If the subject is shared and the connective is and with a tight relation, omit the comma. Adverb-joined clauses take semicolons, not commas.
5. Do not splice independent clauses with a comma. Use a semicolon, a comma + conjunction, or a period. Allowed exception: short, parallel clauses (Man proposes, God disposes.). Adverbial joiners (accordingly, besides, then, therefore, thus) still need a semicolon.
6. Do not break a sentence with a period where a comma belongs. Sentence fragments only for deliberate emphasis (Again and again he called out. No reply.) — and only when no reader will mistake them for a slip.
7. Opening participial phrase must refer to the grammatical subject. Same for opening adjective phrases, appositives, and prepositional participials. Walking slowly down the road, he saw a woman… not …the clock struck twelve.

Ch. III — Elementary principles of composition

8. One paragraph per topic. Do not split one idea across paragraphs; do not merge topics.
9. Topic sentence near the start; close in conformity with it. Don't end on digression or unimportant detail.
10. Active voice. Replace there is/are/were, could be heard, and noun-subjects-of-passives that swallow their own action:
    • There were a great number of dead leaves lying on the ground. → Dead leaves covered the ground.
    • A survey of this region was made in 1900. → This region was surveyed in 1900.
    • The reason that he left college was that his health became impaired. → Failing health compelled him to leave college. Passive is fine when the right word needs to be subject. Never stack two passives.
11. Positive form. Use not for denial or antithesis, never evasion.
    • not honest → dishonest; not important → trifling; did not remember → forgot; did not pay any attention to → ignored; did not have much confidence in → distrusted; He was not very often on time. → He usually came late.
12. Definite, specific, concrete. Prefer specific over general, definite over vague, concrete over abstract.
    • A period of unfavorable weather set in. → It rained every day for a week.
    • He showed satisfaction as he took possession of his well-earned reward. → He grinned as he pocketed the coin.
13. Omit needless words. Vigorous writing is concise. Standard cuts:
    • the question as to whether → whether
    • there is no doubt but that → doubtless
    • used for fuel purposes → used for fuel
    • he is a man who → he
    • in a hasty manner → hastily
    • this is a subject which → this subject
    • His story is a strange one. → His story is strange.
    • the fact that — revise out every occurrence (owing to the fact that → because; in spite of the fact that → though; call your attention to the fact that → remind you; the fact that he had not succeeded → his failure; the fact that I had arrived → my arrival).
    • who is, which was — usually superfluous (his brother, who is a member of the same firm → his brother, a member of the same firm).
    • Collapse clause-chains: combine sequences of short sentences that develop a single thought into one denser sentence.
14. Vary sentence shapes. A run of loose, two-clause sentences joined by and / but / so / who / which becomes monotonous. Mix simple, periodic, and semicolon-joined forms.
15. Parallel construction for coordinate ideas.
    • Formerly, science was taught by the textbook method, while now the laboratory method is employed. → Formerly, science was taught by the textbook method; now it is taught by the laboratory method.
    • Article or preposition before a series: use once before the first item, or repeat before each (The French, the Italians, the Spanish, and the Portuguese).
    • Correlatives (both/and, not/but, not only/but also, either/or, first/second/third) take matching grammatical parts on both sides.
16. Keep related words together.
    • Don't split subject and verb with a transferable phrase. Wordsworth, in the fifth book of The Excursion, gives… → In the fifth book of The Excursion, Wordsworth gives…
    • Relative pronoun follows its antecedent immediately when possible.
    • Modifiers next to what they modify: He found only two mistakes, not He only found two mistakes. Not all the members were present, not All the members were not present.
17. One tense per summary. Drama → present. Story/novel/poem → present preferred, past allowed; antecedent action takes the perfect (present-tense summary) or past perfect (past-tense summary). Past tense inside indirect discourse stays past. Don't intercalate he said, the author then adds.
18. Place the emphatic words at the end. The strongest position is sentence-final; second-strongest is sentence-initial. The end-weight rule scales: words within a sentence, sentences within a paragraph, paragraphs within a piece.

Ch. IV — A few matters of form

• Numerals: do not spell out dates or serial numbers — August 9, 1918; Rule 3; Chapter XII; 352nd Infantry.
• Parentheses: punctuate the outer sentence as if the parenthetical were absent. Punctuate the inner expression as if standalone, but omit its final stop unless it's ? or !. A wholly detached parenthetical sentence keeps its stop inside the closing paren.
• Quotations:
  • Formal cited quotation → colon + quotation marks.
  • Quotation in apposition or as direct object → comma + quotation marks.
  • Quotation introduced by that → indirect discourse, no quotation marks.
  • Verse quotation of a line or more → on its own line(s), centered, no quotation marks.
  • Proverbial / familiar / colloquial / slang phrases → no quotation marks.
• Titles: italics with capitalized initials (The Iliad, As You Like It, A Tale of Two Cities). Drop initial A/The when a possessive precedes (Dickens's Tale of Two Cities).
• References: parenthesize or footnote, don't inline. Abbreviate frequent titles. Omit act, scene, line, book, volume, page when at least one is given numerically (III.ii, IV.ii.14).

Ch. V — Words and expressions commonly misused (silent substitutions)

• all right — two words; avoid outside familiar speech.
• as good or better than X → as good as X, or better.
• as to whether → whether.
• bid — takes infinitive without to; past tense (= ordered) is bade.
• but — unneeded after doubt and help (I have no doubt but that → I have no doubt that). Avoid stacking but … But …; rearrange.
• can — = able; not a substitute for may (= permitted).
• case — usually deletable (In many cases, the rooms were poorly ventilated → Many of the rooms were poorly ventilated).
• certainly — drop as filler intensifier.
• character — usually redundant (acts of a hostile character → hostile acts).
• claim (v.) — only for lay claim to; not for declare, maintain, charge.
• clever — restrict to small-scale ingenuity.
• compare to = point out resemblance between different orders; compare with = point out differences between same order.
• consider (= believe to be) — no as. I consider him competent, not as competent.
• data, phenomena, strata — plural. These data were tabulated.
• dependable → reliable, trustworthy.
• different than → different from (or other than, unlike).
• divided into ≠ composed of.
• don't = do not; doesn't = does not. Don't substitute one for the other.
• due to — not for because of / owing to in adverbial use. Correct: predicate adjective tied to a specific noun (losses due to preventable fires).
• effect (n. = result; v. = bring about) ≠ affect (= influence). Drop as vague filler (subtle effects, charming effect).
• etc. — never after such as / for example. Use only when the remainder is obvious.
• fact — only for matters capable of direct verification. See Rule 13 for the fact that.
• factor, feature — hackneyed; rewrite (The great factor in his winning was his training → He won by being better trained).
• fix — colloquial for arrange/mend; in writing use only fasten, make firm.
• folk — collective, singular form.
• get / have got → have. Participle: got.
• he is a man who — redundant.
• however (= nevertheless) — never first in its clause. (However first means in whatever way or to whatever extent.)
• interesting — show, don't announce.
• kind of, sort of — not for rather; restrict to literal classification.
• less vs fewer: less = quantity; fewer = number. Exception: less than a hundred-style round numbers.
• like governs nouns/pronouns; before clauses use as (He thought as I did — like me is OK).
• line, along these lines — overworked; cut.
• literal, literally — only for actual literalness.
• lose out, try out, win out, sign up, register up — drop the out / up.
• most ≠ almost (most everybody → almost everybody).
• nature — usually redundant; otherwise specify the kind of nature meant.
• near by — as adverb prefer near or near at hand; as adjective use neighboring.
• oftentimes, ofttimes → often.
• one hundred and one — keep the and.
• one of the most — don't open with it; threadbare. A relative clause after it takes a plural verb (one of the ablest men that have attacked this problem).
• participle for verbal noun — possessive before the gerund: Do you mind my asking?, prospect of the Senate's accepting. (Don't force when meaning targets the subject, not the action.)
• people (political) ≠ public (artistic / commercial).
• phase — only stage of transition; not aspect or topic.
• possess — not a fancy have / own.
• prove — past participle proved.
• respective, respectively — usually drop.
• shall / will — see Era caveats above; do not impose 1918 distinction.
• so — avoid as bare intensifier (so good, so warm).
• split infinitive — avoid (to diligently inquire → to inquire diligently).
• state — only express fully or clearly; not a substitute for say, remark.
• student body → students.
• system — drop when bare (the dormitory system → dormitories; the commission system of government → government by commission).
• thanking you in advance — drop; rewrite as Will you please… or I shall be obliged….
• they — see Era caveats above; do not impose 1918 he.
• very — sparingly; prefer a stronger word.
• viewpoint → point of view; not a synonym for view or opinion.
• while — only for during the time that. Replace with and, but, although, or a semicolon for the looser senses.
• whom / who — whom only when object. His brother, who he said would send him the money (not whom).
• worth while — only of actions, never before a noun. His books are not worth reading (not not worth while).
• would / should — 1st-person conditional = should. Habitual past: drop would and use plain past (Once a year he visited the old mansion).

Ch. VI — Spelling

• Modern spelling. Override Strunk on: today, tonight, tomorrow (no hyphen).
• Keep two-word forms: any one, every one, some one, some time (in the sense "an indefinite period" — but sometime meaning "formerly" is one word).
• Doubling: a single final consonant (not v) preceded by a stressed short vowel doubles before -ed / -ing — planned, letting, beginning. Coming is an exception.
• Watch the standard misspelled list: accidentally, advice, affect, believe, benefit, challenge, coarse, course, criticize, deceive, definite, describe, despise, develop, disappoint, dissipate, ecstasy, effect, embarrass, existence, fascinate, fiery, formerly, humorous, hypocrisy, immediately, impostor, incident, incidentally, latter, led, lose, marriage, mischief, murmur, necessary, occurred, opportunity, parallel, playwright, preceding, prejudice, principal / principle, privilege, pursue, repetition, rhyme, rhythm, ridiculous, sacrilegious, seize, separate, shepherd, siege, similar, simile, too, tragedy, tries, undoubtedly, until, villain.

Procedure

1. Resolve input: existing file path → Read it; otherwise treat the argument as raw text.
2. Identify and lock preserve-verbatim regions (code, URLs, quotes, tables).
3. Rewrite the remaining prose sentence by sentence. Useful order: 13 (cut) → 10 (active) → 11 (positive) → 12 (concrete) → 3/4/5 (commas, semicolons) → 16 (word order) → 15 (parallelism) → 18 (end-weight) → 7 (danglers) → 14 (vary shapes) → 17 (tense) → 1/2 (apostrophes, series commas) → Ch. V substitutions → Ch. IV form → Ch. VI spelling.
4. Re-stitch preserved regions back in.
5. Print the result. Nothing else.