Prefixes – Suffixes

Suffixes change word class, e.g. from verb to noun or noun to adjective, but they can also change meaning (see sections B and C below).

Noun or verb + suffix

Noun or Verb	Suffix	Adjectives
danger, fame	-ous	dangerous, famous (= well-known)
music, politics industry, economics	-al	musical, political, industrial, economical (= saves you money)
cloud, fog, sun, dirt	-y	cloudy, foggy, sunny, dirty (not clean)
attract, create	-ive	attractive (= pretty, nice to look at); creative (= ableto produce new ideas; with imagination)

Note: Sometimes there is a spelling change. Here are common examples:

double the consonant,

• sun/sunny,
• fog/foggy

leave out the final ‘e’,

• create/creative,
• fame/famous

leave out the final’s’ before ‘al’,

• politics/political;
  
• economics/economical

change ‘y’ to ‘i’ before ‘al’,

• industry/industrial

-able /abl/

This suffix (also -ible in some words) is used to form many adjectives from nouns or verbs:

• enjoyable
  
• comfortable
  
• knowledgeable (= knows a lot)
  
• suitable (= right/correct for a particular situation)

Quite often, -able (and -ible) has the meaning ‘can be done’.

• Something that is washable ‘can be washed’.
  
• drinkable
• comprehensible (= can be comprehended or understood)
• reliable (= can be relied on or trusted, e.g. a car or other machine that never goes wrong or breaks down).

Words ending -able quite often express the opposite meaning by adding the prefix un-:

• undrinkable
• unreliable
• unbreakable (= cannot be broken)
• unsuitable
• uncomfortable

Words ending –ible add the prefix in-:

• incomprehensible
• inflexible (somebody who is inflexible has a fixed idea about something and cannot change quickly or easily; an inflexible timetable cannot be changed easily)
• inedible (= cannot be eaten).

-ful and -less

The suffix -ful often means ‘full of + the meaning of the adjective:

• careful, you are full of care
• if you are helpful you are full of help.
• painful (= hurts a lot)
  
• useful
• thoughtful (= someone who is thoughtful is kind and always thinks about others; a thoughtful action shows care for others)

The suffix -less means ‘without’ + the meaning of the adjective:

• if you are careless, you do something ‘without care’.
• painless, useless (= has no use or function) thoughtless, jobless and homeless (= with nowhere to live)

Note: You can see that -ful and -less are often used with the same words to form opposites. This is not always true: a person with a home is NOT homcful.

Suffixes come at the end of words. They help you to understand the meaning of a new word. Here are some common suffixes.

suffix	meaning	examples
er, or (noun)	person	worker, swimmer, instructor
er, or (noun)	machine, thing	cooker, word processor
ful (adjective)	full of	useful, beautiful
ology (noun)	subject of study	sociology, psychology
ics (noun, singular)	subject of study	economics, politics
less (adjective)	without	useless, endless
ly	makes an adverb from an adjective	sadly, happily
ness	makes an abstract noun from an adjective	happiness, sadness
y	makes an adjective from a noun	sandy, sunny

– able

• available believable miserable

– ance

• observance observance instance

– ary

• infirmary honorary imaginary

– ent

• judgment dependent confident

– ence

• indulgence independence silence

– ery

• slavery pottery lottery

– dom

• freedom kingdom wisdom

– er

• lecturer manager teacher

– ment

• attachment disappointment loneliness

– ness

• politeness happiness equipment

– ture

• fixture mixture signature

– ure

• brochure denture moisture

– ion

• communion complexion opinion

– ition

• intuition competition repetition

– tion

• election production education

– ious

• furious mysterious rebellious

– ise

• expertise exercise

– ize

• summarize memorize

– ant

• reluctantant protestant silent

– ible

• digestible flexible sensible

– ory

• observatory laboratory sensory

– ian

• comedian electrician politician

– or

• creator adjudicator spectator

– ation

• aviation transportation reservation

– sion

• abrasion discussion television

– ous

• furious joyous nervous

– less

• faithless careless

Prefixes (at the beginning of words) can help you to understand what a new word means. Here are some common prefixes.

un- and dis-

These prefixes have two meanings: they can have a negative meaning (as above), but they can also mean ‘the opposite of an action’ or ‘to reverse an action’. This meaning is used with certain verbs.

• I locked the door when I left, but I lost the key, so I couldn’t it unlock it when I got back.
• I had to pack my suitcase (= put everything in it) very quickly, so when I unpacked (= took everything out) at the hotel, most of my clothes looked terrible.
• The plane appeared in the sky, then suddenly disappeared behind a cloud.
• In the morning you get dressed (= put on your clothes); when you go to bed you get undressed (= take off your clothes).

re- (= again)

• My homework was terrible, so I had to redo it.

• The shop closed down but will reopen next month.

• I failed my exam but I can retake (or redo/resit) it next year.

over- (= too much)

• I think my boss is overdoing it at the moment. (= working too hard; also overwork)

• I went to bed very late and I overslept (= slept too long) this morning.

• The shop assistant overcharged me. (= asked me for too much money)

mis- (= badly or incorrectly)

• I’m afraid I misunderstood what he said.
• Two of the students misread the first question.

Prefix	Meaning	Example
a	not	aseptic, asymmetrical
ab	away from	abnormal, absent
anti	against	antibiotic, antifreeze
auto Read morePrefixes often used

A, AN–  not, without

amoral, atrophy, asymmetrical, anarchy, anesthetic, anonymity, anomaly

AB, A–  from, away, apart

abnormal, abdicate, aberration, abhor, abject, abjure, abortive, abrogate, abscond, absolve, abstemious, annul, avert, aversion

AC, ACR–  sharp, sour

acid, acerbic, exacerbate, acute, acuity, acumen, acrid, acrimony

AD, A- to, toward

adhere, adjacent, adjunct, admonish, adroit, advent, abeyance, abet, accede, acquiesce, affluent, aggrandize, aggregate, alleviate, allude,  ascribe, aspersion, aspire, assail, attest

ALl, ALTR–  another

alias, alienate, inalienable, altruism

AM, AMI–  love

amorous, amicable, amiable, amity

AMBI, AMPHI–  both

ambiguous, ambivalent, ambidextrous, amphibious

AMBL, AMBUL–  walk

amble, ambulatory, perambulator, somnambulist

ANIM- mind, spirit, breath

animal, animosity, unanimous, magnanimous

ANN, ENN–  year

annual, annuity, superannuated, biennial, perennial

ANTE, ANT-before

antecedent, antediluvian, antebellum, antepenultimate, anterior, antiquity, antiquated, anticipate

ANTHROP–  human

anthropology, anthropomorphic, misanthrope, philanthropy

ANTI, ANT–  against, opposite

antidote, antipathy, antithesis, antacid, antagonist, antonym

AUD- hear

audio, audience, audition, auditory, audible

AUTO–  self

autobiography, autocrat, autonomous

BELLI, BELL–  war

belligerent, bellicose, antebellum, rebellion

BENE, BEN–  good

benevolent, benefactor, beneficent, benign

BI–  two

bicycle, bisect, bilateral, bilingual, biped

BIBLIO- book

Bible, bibliography, bibliophile

BIO–  life

biography, biology, amphibious, symbiotic, macrobiotics

BURS–  money, purse

reimburse, disburse, bursar

CAD, CAS, CID–  happen, fall

accident, cadence, cascade, deciduous

CAP, CIP–  head

captain, decapitate, capitulate, precipitous, precipitate

CAP, CAPT, CEPT, CIP–  take, hold, seize

capable, recapitulate, captivate, deception, intercept, precept, inception, anticipate,

emancipation, incipient, cede, precede, accede, recede, antecedent, intercede, secede

CARN- flesh

carnal, carnage, carnival, carnivorous, incarnate

CED, CESS–  yield, go

cease, cessation, incessant, cede

CHROM—  color

chrome, chromatic, monochrome

CHRON–  time

chronology, chronic, anachronism

CIDE–  murder

suicide, homicide, regicide, patricide

CIRCUM–  around

circumference, circumlocution, circumnavigate, circumscribe, circumspect, circumvent

CLIN, CLIV–  slope

incline, declivity, proclivity

CLUD, CLUS, CLAUS, CLOIS–  shut, close

conclude, reclusive, claustrophobia, cloister, preclude, occlude

CO, COM, CON–  with, together

coeducation, coagulate, coalesce, coerce, cogent, cognate, collateral, colloquial, commensurate,  compassion, compatriot, complacent, compliant, complicity, compunction, conciliatory, concord, concur, condone, conflagration, congeal, congenial, congenital, conglomerate, conjure, conjugal, conscientious, consecrate, consensus, consonant, constrained, contentious, contrite, convalescence, convene, convivial, convoke, convoluted, congress

COGN, GNO–  know

recognize, cognition, cognizance, incognito, diagnosis, agnostic, prognosis, gnostic, ignorant

CONTRA- against

controversy, incontrovertible, contravene

CORP –  body

corpse, corporeal, corpulence

COSMO, COSM–  world

cosmopolitan, cosmos, microcosm, macrocosm

CRAC, CRAT –  rule, power

democracy, bureaucracy, theocracy, autocrat, aristocrat, technocrat

CRED- trust, believe

incredible, credulous, credence

CRESC, CRET –  grow

crescent, crescendo, accretion

CULP–  blame, fault

culprit, culpable, inculpate, exculpate

CURR, CURS–  run

current, concur, cursory, precursor, incursion

DE–  down, out, apart

depart, debase, debilitate, decry, deface, defamatory, defunct, delegate, demarcation, demean, demur, deplete, deplore, depravity, deprecate, deride, desist, detest, devoid

DEC- ten, tenth

decade, decimal, decathlon, decimate

DEMO, DEM–  people

democrat, demographics, demagogue, epidemic, pandemic, endemic

DI, DIURN–  day

diary, diurnal, quotidian

DIA- across

diagonal, diatribe

DIC, DICT –  speak

diction, interdict, predict, abdicate, indict, verdict

DIS, DIF, DI–  not, apart, away

disaffected, disband, disbar, disburse, discern, discordant, discredit, disheveled, disparage, disparate, dispassionate, dispirit, dissemble, disseminate, dissension, dissipate, dissonant, dissuade, distend, differentiate, diffidence, diffuse, digress, divert

DOC, DOCT –  teach

doctrine, docile

DOL- pain

condolence, doleful, dolorous, indolent

DUC, DUCT–  lead

seduce, induce, conduct, viaduct, induct

EGO- self

ego, egoist, egocentric

EN, EM–  in, into

enter, entice, encumber, endemic, ensconce, enthrall, entreat, embellish, embezzle, embroil,

empathy

ERR–  wander

erratic, aberration, errant

EU–  well, good

eulogy, euphemism, euphony, euphoria, eurythmics, euthanasia

EX, E- out, out of

exit, exacerbate, excerpt, excommunicate, exculpate, exhume, exonerate, exorbitant, exorcise, expatriate, expedient, expiate, expunge, expurgate, extenuate, extort, extremity, extricate,

extrinsic, exult, evoke, evict, elicit, egress, egregIous

FAC, FIC, FECT, FY, FEA–  make, do

factory, facility, benefactor, malefactor, fiction, fictive, beneficent, affect, magnify, unify, rectify, vilify, feasible

FAL, FALS–  deceive

false, infallible, fallacious

FERV – boil

fervent, fervid, effervescent

FLU, FLUX–  flow

fluent, flux, affiuent, confluence, effluvia, superfluous

FORE–  before

forecast, foreboding, forestall

FRAG, FRAC–  break

fragment, fracture, diffract, fractious, refract

FUS- pour

profuse, infusion, effusive, diffuse

GEN- birth, class, kin

generation, congenital, homogeneous, heterogeneous, ingenious, engender, progeny

GRAD, GRESS–  step

graduate, gradual, retrograde, centigrade, degrade, gradation, gradient, progress, digress, transgress

GRAPH, GRAM–  writing

biography, bibliography, epigraph, grammar, epigram

GRAT –  pleasing

grateful, gratitude, gratis, ingrate, congratulate, gratuitous, gratuity

GRAY; GRIEV–  heavy

grave, gravity, aggravate, grieve, aggrieve, grievous

GREG–  crowd, flock

segregate, gregarious, egregious, congregate, aggregate

HABIT, HIBIT –  have, hold

habit, inhibit, cohabit, habitat

HAP– by chance

happen, haphazard, hapless, mishap

HELlO, HELl–  sun

heliocentric, helium, heliotrope, aphelion, perihelion

HETERO–  other

heterosexual, heterogeneous, heterodox

HOL–  whole

holocaust, catholic, holistic

HOMO–  same

homosexual, homogenize, homogeneous, homonym

HOMO–  man

homo sapiens, homicide, bonhomie

HYDR–  water

hydrant, hydrate, dehydration

HYPER–  too much, excess

hyperactive, hyperbole, hyperventilate

HYPO–  too little, under

hypodermic, hypothermia, hypochondria, hypothesis, hypothetical

IN, IG, IL, IM, IR–  not

incorrigible, indefatigable, indelible, inept, inert, inexorable, insatiable, insentient,  insolvent, insomnia, interminable, intractable, incessant, inextricable, infallible, infamy, inoperable, insipid, intemperate, intrepid, inviolable, ignorant, ignominious, ignoble,  illicit, immaculate, immutable, impasse, impeccable, impertinent,  implacable, impotent, impregnable, impassioned, impervious, irregular, invade, incandescent, incarcerate, incense, indenture, induct, ingratiate, introvert, inception, incisive, infer

IN, IL, IM, IR–  in, on, into

infusion, innate, inquest, inscribe, insinuate, inter, illustrate, imbue, immerse, implicate, irrigate, irritate

INTER- between, among

intercede, intercept, interject, interlocutor, interloper, intermediary, intermittent, interpolate, interpose, interrogate, intersect, intervene

INTRA, INTR–  within

intrastate, intravenous, intramural, intrinsic

IT, ITER–  between, among

transit, itinerant, reiterate, transitory

JECT, JET–  throw

eject, interject, abject, trajectory, jettison

JOUR–  day

journal, adjourn, sojourn

JUD–  judge

judge, judicious, prejudice, adjudicate

JUNCT, JUG–  join

junction, adjunct, injunction, conjugal, subjugate

JUR–  swear, law

jury, abjure, adjure, conjure, perjure, jurisprudence

LAT –  side

lateral, collateral, unilateral, bilateral, quadrilateral

LEG, LEC, LEX–  read, speak

legible, lecture, lexicon

LEV–  light

elevate, levitate, levity, alleviate

LIBER- free

liberty, liberal, libertarian, libertine

LIG, LI, LY–  bind

ligament, oblige, religion, liable, liaison, lien, ally

LING, LANG–  tongue

lingo, language, linguistics, bilingual

LITER- letter

literate, alliteration, literal

LITH–  stone

monolith, lithograph, megalith

LOQU, LOC, LOG–  speech, thought

eloquent, loquacious, colloquial, soliloquy, circumlocution, interlocutor, monologue,

dialogue, eulogy, philology, neologism

LUC, LUM–  light

lucid, illuminate, elucidate, translucent

LUD, LUS–  play

ludicrous, allude, delusion, allusion, illusory

MACRO–  great

macrocosm, macrobiotics

MAG, MAJ, MAS, MAX–  great

magnify, majesty, master, maximum, magnanimous, magnate, magnitude

MAL–  bad

malady, maladroit, malevolent, malodorous

MAN- hand

manual, manuscript, emancipate, manifest

MAR- sea

submarine, marine, maritime

MATER, MATR–  mother

maternal, matron, matrilineal

MEDI- middle

intermediary, medieval, mediate

MEGA–  great

megaphone, megalomania, megalith

MEM, MEN–  remember

memory, memento, memorabilia, reminisce

METER, METR, MENS- measure

meter, thermometer, perimeter, metronome, commensurate

MICRO–  small

microscope, microorganism, microcosm, microbe

MIS–  wrong, bad, hate

misunderstand, misanthrope, misapprehension, misconstrue, misnomer, mishap

MIT, MISS–  send

transmit, emit, missive

MOLL- soft

mollify, emollient, mollusk

MON, MONIT–  warn

admonish, monitor, premonition

MONO–  one

monologue, monotonous, monogamy, monolith, monochrome

MOR, MORT –  dead

morbid, moribund, mortal, amortize

MORPH–  shape

amorphous, metamorphosis, morphology

MOY, MOT, MOB, MOM–  move

remove, motion, mobile, momentum, momentous

MUT – change

mutate, mutability, immutable, commute

NAT, NASC–  born

native, nativity, natal, neonate, innate, cognate, nascent, renaissance

NEG- not, deny

negative, abnegate, renege

NEO- new

neoclassical, neophyte, neologism, neonate

NIHIL–  none, nothing

annihilation, nihilism

NOM, NYM–  name

nominate, nomenclature, nominal, cognomen, misnomer, ignominious, antonym, homonym,

pseudonym, synonym, anonymity

NOX, NIC, NEC, NOC–  harm

obnoxious, noxious, pernicious

NOY–  new

novelty, innovation

NUMER–  number

numeral, numerous, innumerable, enumerate

OB- against

obstruct, obdurate, obfuscate, obnoxious, obsequious, obstinate, obtrusive

OMNI- all

omnipresent, omnipotent, omniscient, omnivorous

ONER- burden

onerous, onus, exonerate

OPER- work

operate, cooperate, inoperable

PAC- peace

pacify, pacifist, pacific

PALP- feel

palpable, palpitation

PAN- all

panorama, panacea, panegyric, pandemic

PATER, PATR–  father

paternal, paternity, patriot, compatriot, expatriate, patrimony, patricide, patrician

PATH, PASS–  feel, suffer

sympathy, antipathy, empathy, apathy, pathos, impassioned

PEC- money

pecuniary, impecunious

PEL, PULS- drive

compel, compelling, expel, propel, compulsion

PEN- almost

peninsula, penultimate, penumbra

PEND, PENS–  hang

pendant, pendulous, compendium, suspense, propensity

PER- through, by, for, throughout

percipient, perfunctory, permeable, perturbation, perusal, perennial

PER- against, destruction

perfidious, pernicious, perjure

PERI- around

perimeter, periphery, peripatetic

PET- seek, go toward

petition, impetus, impetuous, petulant, centripetal

PHIL- love

philosopher, philanderer, philanthropy, bibliophile, philology

PHOB- fear

phobia, claustrophobia, xenophobia

PHON- sound

phonograph, megaphone, euphony, phonetics, phonics

PLAC–  calm, please

placate, implacable, placid, complacent

PON, POS- put, place

postpone, proponent, exponent, preposition, posit, interpose, juxtaposition, depose

PORT- carry

portable, deportment, rapport

POT – drink

potion, potable

POT- power

potential, potent, impotent, potentate, omnipotence

PRE- before

precede, precipitate, preclude, precocious, precursor, predilection, predisposition, preponderance,

prepossessing, prescient, prejudice, predict, premonition, preposition

PRIM, PRI- first

prime, primary, primal, primeval, primordial, pristine

PRO- ahead, forth

proceed, proclivity, procrastinator, profane, profuse, progenitor, progeny, prognosis, prologue,

propel, proponent, propose, proscribe, protestation, provoke

PROTO- first

prototype, protagonist, protocol

PROX, PROP- near

approximate, propinquity, proximity

PSEUDO- false

pseudoscientific, pseudonym

PYR- fire

pyre, pyrotechnics, pyromania

QUAD, QUAR, QUAT-four

quadrilateral, quadrant, quadruped, quarter, quarantine, quaternary

QUES, QUER, QUIS, QUIR–  question

quest, inquest, query, querulous, inquisitive

QUIE- quiet

disquiet, acquiesce, quiescent, requiem

QUINT, QUIN–  five

quintuplets, quintessence

RADI, RAMI–  branch

radius, radiate, radiant, eradicate, ramification

RECT, REG–  straight, rule

rectangle, rectitude, rectify, regular

RETRO- backward

retrospective, retroactive, retrograde

RID, RIS–  laugh

ridiculous, deride, derision

ROG- ask

interrogate, derogatory, abrogate, arrogant

RUD- rough, crude

rude, erudite, rudimentary

RUPT – break

disrupt, interrupt, rupture

SACR, SANCT–  holy

sacred, sacrilege, consecrate, sanctify, sanction, sacrosanct

SCRIB, SCRIPT, SCRIV –  write

scribe, ascribe, circumscribe, inscribe, proscribe, script, manuscript, scrivener

SE- apart, away

separate, segregate, secede, sedition

SEC, SECT, SEG—  cut

sector, dissect, bisect, intersect, segment, secant

SED, SID–  sit

sedate, sedentary, supersede, reside, residence, assiduous, insidious

SEM–  seed, sow

seminar, seminal, disseminate

SEN- old

senior, senile, senescent

SENT, SENS- feel, think

sentiment, nonsense, assent, sentient, consensus, sensual

SEQU, SECU–  follow

sequence, sequel, subsequent, obsequious, obsequy, non sequitur, consecutive

SIGN–  mark, sign

signal, designation, assignation

SIM, SEM–  similar, same

similar, semblance, dissemble, verisimilitude

SOL- sun

solar, parasol, solarium, solstice

SOL- alone

solo, solitude, soliloquy

SOMN- sleep

insomnia, somnolent, somnambulist

SON–  sound

sonic, consonance, dissonance, assonance, resonate

SOPH–  wisdom

philosopher, sophistry, sophisticated, sophomoric

SPEC, SPIC–  see, look

spectator, circumspect, retrospective, perspective

SPER–  hope

prosper, prosperous, despair, desperate

SPERS, SPAR–  scatter

disperse, sparse, aspersion, disparate

SPIR–  breathe

respire, inspire, spiritual, aspire, transpire

STRICT, STRING–  bind

strict, stricture, constrict, stringent, astringent

STRUCT, STRU–  build

structure, construe, obstruct

SUB–  under

subconscious, subjugate, subliminal, subpoena, subsequent, subterranean, subvert

SUMM- highest

summit, summary, consummate

SUPER, SUR–  above

supervise, supercilious, supersede, superannuated, superfluous, insurmountable, surfeit

SURGE, SURRECT –  rise

surge, resurgent, insurgent, insurrection

SYN, SYM- together

synthesis, sympathy, synonym, synopsis, symposium, symbiosis

TACIT, TIC–  silent

tacit, taciturn, reticent

TACT, TAG, TANG–   touch

tact, tactile, contagious, tangent, tangential, tangible

TEN, TIN, TAIN–  hold, twist

detention, tenable, tenacious, pertinacious, retain

TEND, TENS, TENT–  stretch

intend, distend, tension, tensile, ostensible, contentious

TERM—  end

terminal, terminate, interminable

TERR– earth, land

terrain, terrestrial, extraterrestrial, subterranean

TEST–  witness

testify, attest, testimonial, testament, detest, protestation

THE- god

atheist, theology, theocracy

THERM–  heat

thermometer, thermal, thermonuclear, hypothermia

TIM- fear, frightened

timid, intimidate, timorous

TOP- place

topic, topography, utopia

TORP- stiff, numb

torpedo, torpid, torpor

TORT- twist

distort, extort, tortuous

TOX- poison

toxic, toxin, intoxication

TRACT –  draw

tractor, intractable, protract

TRANS–  across, over, through, beyond

transport, transgress, transient, transitory, translucent, transmutation

TREM, TREP–  shake

tremble, tremor, tremulous, trepidation, intrepid

TURB- shake

disturb, turbulent, perturbation

UMBR- shadow

umbrella, umbrage, adumbrate, penumbra

UNI, UN- one

unify, unilateral, unanimous

URB– city

urban, suburban, urbane

VAC-empty

vacant, evacuate, vacuous

VAL, VAIL–  value, strength

valid, valor, ambivalent, convalescence, avail, prevail, countervail

VEN, VENT —  come

convene, contravene, intervene, venue, convention, circumvent, advent

VER–  true

verify, verity, verisimilitude, veracious, aver, verdict

VERB- word

verbal, verbose, verbiage, verbatim

VERT, VERS–  turn

avert, convert, pervert, revert, incontrovertible, divert, subvert, versatile, aversion

VICT, VINC–  conquer

victory, conviction, evict, evince, invincible

VID, VIS–  see

evident, vision, visage, supervise

VIL- base, mean

vile, vilify, revile

VIV; VIT – life

vivid, vital, convivial, vivacious

VOC, VOK, VOW–  call, word

vocal, equivocate, vociferous, convoke, evoke, invoke, avow

VOL–  wish

voluntary, malevolent, benevolent, volition

VOLV; VOLUT –  turn, roll

revolve, evolve, convoluted

VOR–  eat

devour, carnivore, omnivorous, voracious

Prefixes (un-, in-, il-, ir-, and dis-) are often used to give adjectives (and some verbs and nouns) a negative meaning. Here are common examples:

happy         unhappy

like (v)       dislike (v)

possible     impossible

legal            illegal (= against the law)

correct      incorrect

regular      irregular, e.g. irregular verbs

un- is used with many different words, e.g. unfriendly, unable, unemployed (= without a job), untidy (= not in order; in a mess)

im- is used before some words beginning with m or p, e.g. impolite (= rude), impatient (somebody who is impatient wants things to happen now; they cannot wait for things)

il- is used before some words beginning with 1, e.g. illegible
(= cannot be read because the writing is very bad)

ir- is only used before some words beginning with r, e.g. irresponsible

dis- is used before some adjectives, e.g. dishonest, and a few verbs, e.g. dislike, disagree

in- is used before a limited number of words, e.g. invisible (= cannot be seen)

Note: A prefix does not normally change word stress,e.g. happy/unhappy; possible/ impossible. But the stress may change if you want to emphasise the negative or opposite:

• A: Was he happy about the change?
• B: No, he was very unhappy about it.