Classification of American English sounds involves place of articulation, manner of articulation, and voicing. The larynx houses the vocal cords, which can be open (voiceless) or closed (voiced). `-V` represents voiceless sounds, while `+V` represents voiced sounds.
Consonants are classified by voicing, place, and manner of articulation. Places of articulation include bilabial, labio-dental, dental, alveolar, palato-alveolar, palatal, velar, labio-velar, and glottal. Manners of articulation include stops, fricatives, affricates, nasals, lateral approximant, and approximant. Examples of stops are /p, b, t, d, k, g, ?/; fricatives are /f, v, θ, ð, s, z, ʃ, ʒ, h/; affricates are /tʃ, dʒ/; nasals are /m, n, ŋ/; lateral approximant is /l/; and approximants are /r, j, w/.
The `/θ/` (devoiced) sound appears in words like three, thank(s), think, theatre/theater, thrill, earthquake, and withdraw, while the `/ð/` (voiced) sound appears in they, that, this, those, without, and within.
The digraph 'th' is commonly pronounced as `/θ/` or `/ð/`. In the initial position, `/ð/` occurs mostly in function words like the and that, while `/θ/` usually appears in content words like theme and think. At the end of words, prediction is difficult, but `/ð/` is more common, especially in verbs. Before 'e' or '-ing', pronunciation is usually `/ð/`, as in loathe. Exceptions include verbs like 'bathe' and the noun 'bath', some names like Thames and thyme, the suffix '-th' applied to numbers like eighth and sixteenth, prefixes like lighthouse and sweetheart, and occasionally silent letters in words like loath and asthma. Other words include thankless, Thacker, and thaumaturgic.
The pronunciation of <-s>, <-es>, and <-ies> endings can be /s/, /z/, or /ɪz/. Examples include /s/ in stops, ants, wants, nuts, Mike’s, and banks; /z/ in nuns, woman’s, men’s, children’s, kids, tables, cars, bangs, and Bob’s; and /ɪz/ in horses and churches. The keys are /s/ after a voiceless consonant, /z/ after a voiced consonant, and /ɪz/ after a sibilant (/s, z, ʃ, ʒ, tʃ, dʒ/).
The pronunciation of <-ed> endings can be /t/, /d/, or /ɪd/. Examples include /t/ in stopped, looked, watched, popped, walked, talked, smoked, developed, and washed; /d/ in judged, rubbed, snowed, tried, and paid; and /ɪd/ in wanted. The keys are /t/ after a voiceless consonant, /d/ after a voiced consonant or vowel, and /ɪd/ after /t/ or /d/. Exceptions include adjectives like wicked and learned, and -edly and -edness (markedly, well-formedness).
Voiced sounds influence voiced endings, and devoiced sounds influence devoiced endings. This applies to plural forms (banks vs. bangs), third-person singular forms (wants vs. feeds), possessive 's (Mike’s vs. Bob’s), and past tense forms (helped vs. rubbed).
Common mistakes by Italians include wrong place of articulation, consonant lengthening, vowel insertion (related to syllable structure and rhythm), and voicing. Fundamental questions involve which organs of speech are involved and how to use them, including where to locate the tongue.
Specific interference issues include sounds that exist in both languages but are articulated differently, such as /t/, /d/, /ŋ/, and /l/, and sounds that do not exist in Italian but are present in English, such as /θ, ð/ () and /r/. For example, /n/ ≠ /ŋ/ (alveolar vs. velar, as in sin vs. sing), /l/ can be clear vs. dark, is often mispronounced as /t/ or /d/ (Thank you -> Tank you), and /r/ can be bunched, retroflex, or trilled.
In English, double consonants are never pronounced, unlike in Italian. English words often end in a closed syllable, unlike Italian (e.g., David, magic, like, love).
The English spelling system does not consistently reflect the pronunciation system, and vice versa. For example, GHOTI = FISH (gh as in rough, o as in women, ti as in nation). Further examples include eight vs. height, Wednesday, child vs. children, Christ vs. Christmas. Place names with irregular pronunciations include Greenwich, Edinburgh, Leicester, Gloucester, Illinois, Missouri, New Jersey, Arkansas, and Tucson.
One consonant sound can have many different graphemes (e.g., = /f/ in laugh). Silent letters are common (p in cupboard, b in thumb, t in castle, k in know, g in gnaw, h in hour, l in calm). Words spelt differently but pronounced the same (hiccough vs. hiccup).
Labiodental fricatives include /f/ (devoiced) in fit, cough, photo, and off, and /v/ (voiced) in voice and of. Alveolar stops/occlusives/plosives include /t/ (devoiced) in tip, Thomas, and little (Italian dental /t/ ≠ English alveolar /t/), and /d/ (voiced) in do, middle, and did (Italian dental /d/ ≠ English alveolar /d/).
Examples of silent letters include p in cupboard, receipt, psalm, psycho, and pneumonia; b in thumb, comb, limb, debt, subtle, and doubt; t in castle and Christmas; k in muscle, know, and knew; g in gnaw and sigh; h in hour, heir, honest, vehicle, exhaust, shepherd, Durham, and Nottingham; and l in stalking, talk, calm, walk, folk, and salmon.
Examples of interference clusters include <r+s>
in corso, corsico, orso, corsa, orso /s/ Vs. cars >