3 Spelling and hyphenation
The chief rules whereby words change form to express a grammatical function are described below. In some cases there are acceptable variant forms in addition to those forms shown.
Verbs of one syllable ending in a single consonant double the consonant when adding -ing or -ed:
beg, begging, begged
rub, rubbing, rubbed
When the final consonant is w, x, or y this is not doubled:
tow, towing, towed
vex, vexing, vexed
When the final consonant is preceded by more than one vowel (other than u in qu), or by a diphthong that represents a long vowel, the consonant is not normally doubled:
appeal, appealing, appealed
boil, boiling, boiled
clean, cleaning, cleaned
conceal, concealing, concealed
reveal, revealing, revealed
Verbs of more than one syllable ending in a single consonant double the consonant when the stress is placed on the final syllable:
allot, allotting, allotted
occur, occurring, occurred
Verbs that do not have stress on the final syllable do not double the consonant:
benefit, benefiting, benefited
budget, budgeting, budgeted
gallop, galloping, galloped
offer, offering, offered
profit, profiting, profited
target, targeting, targeted
input, inputting, inputted
output, outputting, outputted
kidnap, kidnapping, kidnapped
worship, worshipping, worshipped
Another exception is focus, focusing, focused, which can double the s as an acceptable alternative: focussing, focused.
Verbs ending in -l normally double the l in British English regardless of where the stress occurs in the word:
annul, annulling, annulled
enrol, enrolling, enrolled
grovel, grovelling, grovelled
travel, travelling, travelled
Exceptions in British English are: parallel, paralleling, paralleled
parallel, paralleling, paralleled
In US English the final l generally doubles only when the stress is on the final syllable. So words such as annul and enrol inflect the same way in America as they do in Britain, but these verbs are different:
grovel, groveling, groveled
travel, traveling, traveled
tunnel, tunneling, tunneled
In some cases US English spells the basic form of the verb with -ll as well (enroll, fulfill).
Note that install has a double l in both British and US English, but instalment has a single l in British spelling and doubles it in US English.
Verbs generally drop a final silent e when the suffix begins with a vowel:
argue, arguing, argued
continue, continuing, continued
But a final e is usually retained to preserve the soft sound of the g in ageing, twingeing, whingeing (but not in US English). Singeing (from singe) and swingeing (from swinge) are thus distinguished from the corresponding forms singing (from sing) and swinging (from swing). Raging is an exception. An e is added to dyeing (from dye) to distinguish it from dying (from die).
A group of verbs—burn, learn, spell—have an orthodox past tense and past participle ending in -ed, but in British English also have an alternative form ending in -t (burnt, learnt, spelt). Note that the past of earn is always earned, never earnt, and that of deal is dealt, not dealed, in both British and US English.
3.2.2 Plurals of nouns
Nouns ending in -y form plurals with -ies (policy, policies), unless the ending is -ey, in which case the plural form is normally -eys (valley, valleys).
Proper names ending in -y retain it when pluralized, and do not need an apostrophe:
the three Marys
Nouns ending in -f and -fe form plurals sometimes with -fs or -fes:
and occasionally both -fs and -ves:
dwarf, dwarfs or dwarves
hoof, hoofs or hooves
For nouns ending in -o there is no fixed system. As a guideline, the following typically form plurals with -os:
• words in which a vowel (usually i or e) precedes the final -o (trios, videos)
• words that are shortenings of other words (demos, hippos)
• words introduced comparatively recently from foreign languages (boleros, placebos)
• words of many syllables (aficionados, manifestos)
• proper names used allusively (Neros, Romeos).
Names of animals and plants normally form plurals with -oes (buffaloes, tomatoes). In other cases practice varies quite unpredictably: kilos and pianos, dominoes and vetoes are all correct. With some words a variant is well established; for example, both mementoes and mementos are used.
Compound words formed by a noun and a following adjective, or by two nouns connected by a preposition, generally form their plurals by a change in the key word:
courts martial or court martials
cul-de-sacs or culs-de-sac
Poets Laureate or Poet Laureates
Plurals of animal names
The plurals of some animal names are the same as the singular forms, for example deer, grouse, salmon, sheep. This rule applies particularly to larger species and especially to those that are hunted or kept by humans. In some contexts the -s is optional: the usual plural of lion is lions, but a big-game hunter might use lion as a plural. For this reason the style is sometimes known as the ‘hunting plural’: it is never applied to small animals such as mice or rats.
The normal plural of fish is fish:
a shoal of fish
he caught two huge fish
The older form fishes may still be used in reference to different kinds of fish: freshwater fishes of the British Isles
freshwater fishes of the British Isles
Plurals of foreign (typically Latin, Greek, or French) words used in English are formed according to the rules either of the original language:
or of English:
Often more than one form is in use:
bureau, bureaus or bureaux
chateau, chateaus or chateaux
crematorium, crematoriums or crematoria
referendum, referendums or referenda
The plural of formula is now more commonly formulas than formulae in British and US English, even in mathematical or chemical contexts. In general the English form is preferred: for example, use stadiums rather than stadia, and forums rather than fora, unless dealing with the ancient world. Incidentally, index generally has the plural indexes in reference to books, with indices being reserved for statistical or mathematical contexts; conversely, appendices tends to be used for subsidiary tables and appendixes in relation to the body part. Always check such words in a dictionary if in any doubt.
Words ending in -is usually follow the original Latin form:
Adjectives that form comparatives and superlatives through the addition of the suffixes -er and -est are:
• words of one syllable (e.g. fast, hard, rich)
• words of two syllables ending in -y and -ly (e.g. angry, early, happy) and corresponding un- forms when these exist (e.g. unhappy). Words ending in -y change the y to i (e.g. angrier, earliest)
• words of two syllables ending in -le (e.g. able, humble, noble), -ow (e.g. mellow, narrow, shallow), and some ending in -er (e.g. clever)
• some words of two syllables pronounced with the stress on the second syllable (e.g. polite, profound)
• other words of two syllables that do not belong to any classifiable group (e.g. common, pleasant, quiet).
Words of one syllable ending in a single consonant double the consonant when it is preceded by a single vowel
glad, gladder, gladdest
hot, hotter, hottest
but not when it is preceded by more than one vowel or by a long vowel indicated by a diphthong
clean, cleaner, cleanest
loud, louder, loudest
Words of two syllables ending in -l double the l in British English: cruel, crueller, cruellest
cruel, crueller, cruellest
Adjectives of three or more syllables use forms with more and most (more beautiful, most interesting, etc.).
Adverbs ending in -ly formed from adjectives (e.g. richly, softly, wisely) generally do not have -er and -est forms but appear as more softly, most wisely, etc. Adverbs that form comparatives and superlatives with -er and -est are:
• adverbs that are not formed with -ly but are identical in form to corresponding adjectives (e.g. runs faster, hits hardest, hold it tighter)
• some independent adverbs (e.g. soon, likely).