Writing rules, made clear
Plain-English guides to the grammar and style rules that quietly cost you marks — each with real before/after examples and a free checker to fix your own writing in one click.
Parallel Structure
Parallel structure means items joined in a sentence share the same grammatical form — all nouns, all -ing verbs, or all clauses. “She likes hiking, swimming, and biking” is parallel; “hiking, swimming, and to bike” is not.
Read the guide →Reduce Wordiness
Wordiness is using more words than your meaning needs. Replace empty phrases with single words — “due to the fact that” becomes “because”, “at this point in time” becomes “now” — and cut words that repeat an idea already stated.
Read the guide →Formal vs Informal Sentences
A sentence is more formal when it avoids contractions, slang, and casual phrasal verbs, and uses precise vocabulary instead. “Kids can’t figure it out” is informal; “Students are unable to understand it” is formal.
Read the guide →Comma Splices
A comma splice happens when two complete sentences (independent clauses) are joined by only a comma. Fix it three ways: a period, a semicolon, or a comma plus a joining word like “and”, “but”, or “so”.
Read the guide →Run-on Sentences
A run-on sentence joins two or more complete thoughts with no punctuation or joining word. Fix it by adding a period, a semicolon, or a comma plus a conjunction between the clauses.
Read the guide →Subject-Verb Agreement
Subject-verb agreement means a singular subject takes a singular verb and a plural subject takes a plural verb. The trap is words between them: “The list of items is long” (the subject is “list”, not “items”).
Read the guide →Active vs Passive Voice
In the active voice the subject does the action (“John threw the ball”). In the passive, the action is done to the subject (“The ball was thrown by John”). Active is usually clearer and shorter; passive has its uses.
Read the guide →Sentence Fragments
A sentence fragment is a group of words punctuated like a sentence but missing a subject, a verb, or a complete thought. “Because it was raining.” is a fragment — it needs a main clause to finish the idea.
Read the guide →Affect vs Effect
Affect is usually a verb meaning to influence (“the weather affects my mood”). Effect is usually a noun meaning the result (“the weather had an effect on my mood”). Memory trick — RAVEN: Remember, Affect is a Verb, Effect is a Noun.
Read the guide →Your vs You’re
Your shows possession (“your book”). You’re is a contraction of “you are” (“you’re late”). The one-second test: if you can expand the word to “you are”, write you’re; if you can’t, write your.
Read the guide →Its vs It’s
It’s (with an apostrophe) is short for “it is” or “it has” (“it’s raining”). Its (no apostrophe) is possessive — something belongs to it (“the dog wagged its tail”). The apostrophe signals a missing letter, not ownership.
Read the guide →There, Their & They’re
There refers to a place or introduces a sentence (“over there”, “there is a problem”). Their shows possession (“their house”). They’re is a contraction of “they are” (“they’re here”).
Read the guide →Who vs Whom
Use who for the subject (the one doing the action) and whom for the object (the one receiving it). Quick test: if the answer is “he/she/they”, use who; if the answer is “him/her/them”, use whom.
Read the guide →To, Too & Two
To is a preposition or part of an infinitive (“to the store”, “to run”). Too means “also” or “excessively” (“me too”, “too hot”). Two is the number 2.
Read the guide →Fewer vs Less
Use fewer for things you can count individually (“fewer cars”, “fewer mistakes”) and less for amounts you can’t count (“less traffic”, “less time”). If you can put a number in front and pluralize it, use fewer.
Read the guide →Dangling Modifiers
A modifier must clearly attach to the word it describes. A dangling modifier opens with a description (“Walking to school,”) but the noun that follows isn’t the one doing it (“the rain started”) — so it seems to modify the wrong thing.
Read the guide →Then vs Than
Than compares (“better than expected”); then marks time or sequence (“finish this, then rest”). Memory trick: thAn = compArison, thEn = timE — if you could swap in “next” or “after that”, the word you need is then.
Read the guide →Semicolon vs Colon
A semicolon joins two complete, closely related sentences (“The road was icy; we drove slowly”). A colon comes after a complete sentence to introduce what follows — a list, an explanation, or a payoff (“She packed three things: rope, tape, and a torch”).
Read the guide →Em Dash
An em dash (—) sets off an interruption, an aside, or a punchline — stronger than commas, less formal than parentheses. In US style it takes no spaces around it, and it works best in moderation: a page peppered with dashes loses the emphasis the dash exists to create.
Read the guide →Lay vs Lie
Lay needs a direct object — you lay something down (“lay the book on the table”). Lie doesn’t — you lie down yourself. The tense trap: the past of lie is lay (lie–lay–lain), while the past of lay is laid (lay–laid–laid).
Read the guide →Fix it as you learn it
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