Comparatives compare two things (taller, more careful); superlatives pick out the extreme among three or more (tallest, most careful). The core choice is length: add -er/-est to short adjectives and put more/most in front of longer ones. A handful of the commonest words are irregular and simply have to be learned: good → better → best, bad → worse → worst.
The single most reliable guide is syllable count.
Several two-syllable adjectives happily take either form, especially those ending in -le, -ow and -er: simpler or more simple, narrower or more narrow, cleverer or more clever, quieter or more quiet. Both are correct — pick whichever reads more smoothly aloud.
Adverbs follow the same logic. Short adverbs that double as adjectives take -er/-est: fast → faster, hard → harder, soon → sooner, early → earlier. But adverbs ending in -ly take more/most: ✓ more quickly, most carefully; ✗ quicklier, carefullier.
These follow no pattern and are worth memorising:
Note that old is regular (older → oldest), but families keep the special forms elder and eldest: my elder brother, the eldest of four. You cannot use elder with than — say he is older than me, never elder than me.
Never double up. The commonest mistake is combining both methods: more easier, most funniest and more better are all wrong. Choose one — easier, funniest, better.
Two things take the comparative. In careful writing, use the comparative for a pair and reserve the superlative for three or more: ✓ the taller of the two teams, not the tallest of the two. That is why we say the better of two options but the best of three.
Than I or than me? Both are fine. She's faster than I (am) is the traditional written form; She's faster than me is standard, natural and correct in all but the most formal contexts. Test it by adding the verb: than I am works, than me am doesn't.
Don't use "very" with a comparative. Intensify with much, far, a lot or even: ✓ much taller, far more expensive; ✗ very taller.
"Absolute" adjectives. Words such as unique, perfect, dead and impossible describe an all-or-nothing state, so strictly they can't be graded — something is unique or it isn't. Careful writers avoid more unique and prefer more nearly unique, or simply unique. Everyday speech breaks this rule constantly, and even the U.S. Constitution promises "a more perfect union" — so treat it as a matter of style, not an iron law.
Fewer vs less. These are the comparatives of few and little. Use fewer for things you can count and less for things you can't: ✓ fewer cars, less traffic; ✗ less cars. The supermarket sign "10 items or less" should really read "or fewer."
Useful patterns. Double a comparative to show change over time: it's getting hotter and hotter, more and more expensive. Pair two comparatives with the … the to link them: the sooner, the better; the more you practise, the easier it gets.
For the two-versus-three problem: "-er for a pair, -est for a crowd." You compare two people to see who is taller, but three or more to find the tallest. For the ending itself: one beat, add the ending; three beats, add the word — one-syllable words earn -er/-est, three-syllable words need more/most, and two-syllable words are the judgement call.
The core rules are identical on both sides of the Atlantic. The one genuine split is farther vs further. Traditionally, farther covers physical distance (ten miles farther down the road) and further covers figurative distance or "additional" (further information, nothing could be further from the truth). American English tends to preserve that distinction; British English increasingly uses further for both. When in doubt, further is the safer choice — it is never wrong for the figurative sense and rarely questioned for the literal one.
A comparative compares two things and usually ends in -er or uses "more" (taller, more careful). A superlative compares three or more and picks out the extreme, ending in -est or using "most" (tallest, most careful), almost always with "the." In short: use the comparative for a pair and the superlative for a group.
Count the syllables. One-syllable adjectives take -er/-est (fast, faster, fastest). Adjectives of three or more syllables take more/most (more beautiful, most beautiful). Two-syllable words vary: those ending in -y use the ending (happier), while most others use more/most (more modern). Some, like simpler and more simple, accept both.
The common irregulars are: good/well → better → best; bad/badly → worse → worst; far → farther/further → farthest/furthest; much/many → more → most; and little → less → least. These follow no pattern and must be memorised. Avoid non-words such as "worser," "baddest," "gooder" or "more better."
No. "More better" is a double comparative and always wrong, because "better" is already the comparative of "good." Never combine "more" with an -er ending, or "most" with an -est ending. Say "better," not "more better"; "easiest," not "most easiest"; "taller," not "more taller."
Use the comparative for two. In careful writing, "the taller of the two" is correct, not "the tallest of the two" — reserve the superlative for three or more. So it is the better of two options but the best of three. Casual speech often uses the superlative, but the comparative is the precise choice.
