Grammar & Usage Guides

Confused by two similar words? We explain the difference between commonly confused words — affect and effect, who and whom, fewer and less — with clear examples of when to use each.

Commonly Confused Words

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affect vs effect

"Affect" is almost always a verb meaning to influence or change something ("The rain affected our plans"). "Ef...

fewer vs less

Use "fewer" for countable things — items you could count one by one ("fewer apples", "fewer people"). Use "les...

who vs whom

Use "who" when it's the subject doing the action ("Who called you?" — he called). Use "whom" when it's the obj...

it's vs its

"It's" (with an apostrophe) is always a contraction of "it is" or "it has" — never possession. "Its" (no apost...

lay vs lie

"Lay" means to put or set something down and needs an object — you lay something ("lay the book down"). "Lie"...

then vs than

Use "than" for comparisons ("faster than", "better than"). Use "then" for time or sequence ("first this, then...

complement vs compliment

A "compliment" (with an I) is a nice thing you say to someone — praise. A "complement" (with an E) is somethin...

imply vs infer

The SPEAKER or writer implies — suggests something without saying it directly ("Her tone implied she was annoy...

Grammar Guides

Grammar Guide A, An, and The: Using Articles Use "a/an" for a non-specific singular noun, "the" when both people know which one, and no... Confused Words Accept vs Except Accept is a verb meaning to receive or agree to something. Except is a preposition meaning... Confused Words Active vs Passive Voice Active voice: the subject does the action. Passive: it receives it (be + past participle).... Confused Words Affect vs Effect Affect is a verb (to influence); effect is a noun (the result). Swap in 'influence' for af... Confused Words Among vs Between Use 'between' for distinct, individual items in a one-to-one relationship (even three or m... Grammar Guide Assure vs Ensure vs Insure Assure a person, ensure a thing happens, insure against loss. That one rule settles almost... Grammar Guide At vs In vs On (Time and Place) 'At' marks a precise time or point (at 6:00, at the door), 'on' a day or surface (on Monda... Confused Words Bring vs Take Use 'bring' for movement toward you and 'take' for movement away — like come vs go. Bring... Confused Words Can vs May Use 'can' for ability and informal permission; 'may' for formal permission and possibility... Grammar Guide Capitalization Rules Capitalize the first word of every sentence, the pronoun I, and all proper nouns: names, p... Punctuation Common Apostrophe Mistakes (and How to Avoid Them) Apostrophes show possession or missing letters — never plurals. The most common mistakes,... Confused Words Commonly Confused Words: a Quick Reference Complement completes; compliment praises. Stationary stands still; stationery is paper. Fe... Grammar Guide Comparatives and Superlatives Add -er/-est to short adjectives (taller) and more/most to longer ones (more careful). Use... Confused Words Complement vs Compliment Complement (with an e) means to complete or pair well with something; compliment (with an... Confused Words Countable vs Uncountable Nouns Countable nouns take many and few (books, ideas); uncountable nouns take much and little (... Grammar Guide Dangling and Misplaced Modifiers A misplaced modifier sits too far from the word it describes; a dangling one describes a w... Grammar Guide Double Negatives In Standard English, two negatives cancel out: "I didn't see nothing" logically means you... Punctuation Em Dash vs En Dash vs Hyphen A hyphen (-) joins words; an en dash (–) spans ranges like 1914–1918; an em dash (—) break... Confused Words Everyday vs Every Day Everyday (one word) = ordinary; every day (two words) = each day. If you can swap in 'each... Confused Words Farther vs Further 'Farther' is for physical distance (two miles farther); 'further' is for figurative distan... Confused Words Fewer vs Less Use 'fewer' for things you can count (fewer books) and 'less' for things you measure (less... Confused Words Gerunds vs Infinitives Use a gerund (-ing) after enjoy, avoid and prepositions; use an infinitive (to + verb) aft... Confused Words Good vs Well 'Good' is an adjective; 'well' is an adverb. Use 'good' after linking verbs (it tastes goo... Punctuation How to Use a Colon A colon introduces a list, explanation, or quotation — and what comes before it must be a...