Irregularities

English has 43.5 sounds

43 as shown in bold letters in the words below

• at, rain, air, car, sauce, bed, chip, dog,      
• egg, eel, herb, fish, garden, house,  
• ink, pie, jug, kite, lips, man, nose, ring, 
• pot, toe, coin, food, wood, order, out,      
• pin, rug, sun, shop, tap, this, thing,     
• up, cue, van, window, yak, zip, television

and an unstressed, often barely audible, variously spelt half-vowel, which occurs mainly in endings and prefixes (fatten, abandon, grammar; decide, divide).

If English had a completely regular spelling system, as Finnish and Korean do,  it would have no more than 44 spellings, and learning to read and write English would be as easy as those two languages. Most alphabetic writing systems, however, do not have a completely one to one relationship between their sounds and spellings, with a few more spellings than sounds.

The European average is around 50. Learning to read and write English is exceptionally difficult because it has 185 spellings for 44 sounds.  

The basic English spelling system has 91 patterns

80 main spellings:

• cat; plate, play; air; car; sauce, saw; bed; c/at/ot/ut, crab/clap, kite/kept, comic, pick, seek, risk; pocket; chat, catch; dog;
• end; eel, funny; herb; fish; garden; house;
• ink; bite, by; jug, bridge, oblige; lips; man; nose; ring;
• pot, want, quarrel; bone, toe, old; coin, toy; food; good; order, wart, quarter, more; out, now;
• pin; quick; rug; sun, face, emergency; shop, station, cautious, facial, musician; tap, delicate; this; thing;
• cup; cube, cue; van, have, river; window; fix; yes; zip, wise; vision, treasure.

8 unstressed endings:

• doable, fatal, single, ordinary, flatten, presence, present, other;

2 prefixes:

• decide, invite;

and the consonant doubling rule for keeping stressed vowels short: 

• bitter – biter.

80 English spelling patterns are undermined by one or more alternatives

• cat: plait, meringue;
• plate: wait, weight, straight, great, vein, reign, table, dahlia, champagne, fete;
• play: they, weigh, ballet, cafe, matinee;
• air: care, bear, aerial, their, there, questionnaire;
• car: are, (Southern Engl. bath);
• sauce: caught, bought, always, tall, crawl;
• saw: (UK also: or, four, more).

• c/at/ot/ut: character, kangaroo, queue;
• crab/clap: chrome;
• lilac: stomach, anorak;
• neck: cheque;
• chat: picture;
• clutch: much;
• dad: blonde;
• end: head, any, said, Wednesday, friend, leisure, leopard, bury;
• her: turn, bird, learn, word, journey;
• eel: eat, even, ceiling, field, police, people, me, key, ski, debris, quay;
• jolly: trolley, movie, corgi.

English spelling makes learning to read harder too

This is partly because children have to learn to pronounce 185 spellings, instead of just around 50. The greatest English reading difficulties, however, are caused by the 69 spellings which have more than one pronunciation, shown in the next table.  They make at least 2000 English words not completely decodable.

69 English spellings have more than one pronunciation

• a: and – apron, any, father
• a-e: came – camera
• ai: wait – plait, said
• al: always – algebra
• all: tall – shall
• are: care – are
• au: autumn – laugh, mauve
• -ate: to deliberate  – a deliberate act
• ay: stays – says
• cc: success – soccer
• ce: centre – celtic
• ch: chop – chorus, choir, chute

• cqu: acquire – lacquer
• e: end – english
• -e: he – the
• ea: mean  – meant, break
• ear: ear – early, heart, bear
• -ee: tree – matinee
• e-e: even – seven, fete
• ei: veil – ceiling, eider, their, leisure
• eigh: weight – height
• eo: people – leopard, leotard
• ere: here – there, were
• -et: tablet – chalet
• eau: beauty – beau
• -ew: few – sew
• -ey: they – monkey

• s: sun – sure;
• sc: scent – luscious, molusc;
• -se: rose – dose;
• ss: possible – possession;
• th: this – thing;
• -ture: picture – mature;
• u: cup – push;
• ui: build – fruit, ruin;

• wa: was – wag;
• wh: what – who;
• wo: won – woman, women, womb;
• wor: word – worn;
• x: box – xylophone, anxious;
• -y-: type – typical;
• --y: daddy – apply;
• z: zip – azure.

• ge: gem – get;
• gi: ginger – girl;
• gy: gym – gynaecologist; 
• ho: house – hour;
• i: ink – kind;
• -ine: define – engine, machine;
• ie: field – friend, sieve;
• imb: limb – climb;
• ign: signature – sign;
• mn: amnesia – mnemonic;

• ost: lost – post;
• -o: go – do;
• oa: road – broad;
• o-e: bone – done, gone;
• -oes: toes – does, shoes;
• -oll: roll – doll;
• omb: tombola – bomb, comb, tomb;
• oo: boot – foot, brooch;
• -ot: despot – depot;
• ou: sound – soup, couple;
• ough: bough – rough, through, trough;
• ought: bought – drought;
• oul: should – shoulder;
• our: sour – four, journey;
• ow: how – low;
• qu: queen – bouquet;

• fish – photo, stuff, rough;
• garden – ghastly, guard;
• house – who;
• ink – mystery, pretty, sieve, women, busy, build;
• bite – might, style, mild, kind, eider, height, climb, island, indict, sign;
• my – high, pie, rye, buy, I, eye;
• jelly,  jig – gentle, ginger;
• fidget – digit;
• kite/kept – chemistry;
• seek – unique;
• risk – disc, mosque;
• lips – llama;
• mum – dumb, autumn;
• nose – knot, gone, gnome, mnemonic;

• on – cough, sausage;
• want – wont;
• quarrel - quod;
• mole – bowl, roll, soul, old, mould, boast, most, goes, mauve;
• toe – go, dough, sew, cocoa, pharaoh, oh, depot;
• oil – oyster;
• toy - buoy;
• food – rude, shrewd, move, group, fruit, truth, tomb, manoeuvre, blue, do, shoe, through;
• good – would, put, woman, courier;
• order – board, court;
• wart, quart – worn, quorn;
• more – soar, door, four, war, swore, abhor;
• out – town;
• now - plough;
• quick – acquire, choir;
• rug – rhubarb, write.