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Back low vowels: /ɔ/ and /ɑ/


 

The cot–caught merger

/ɔ/ and /ɑ/ are back vowels, where the tongue is low. Before we learn how to pronounce /ɔ/ and /ɑ/, we need to know this fact: in standard American English, many words that used to be  pronounced with /ɔ/ are pronounced with /ɑ/. This phenomenon is called the cot–caught merger.  


Areas  in the US where there is no-merger, ‘cot’ and ‘caught’ are pronounced as /kɑt/ and /kɔt/. But in standard american english, they sound the same, /kɑt/. Due to the merger, in standard American English, these words are homophones:


Homophones due to /ɔ/ and /ɑ/ merger

cot - caught

collar - caller

don (put clothes on) - Don (nickname of Donald) - dawn

knotty - naughty

not - naught

rot - wrought 

stock - stalk 

tot (very young child) - taught

nod- gnawed

English Pronunciation, the American Way


Pronunciation of /ɔ/ 

Due to the cot-caught merger, words with the pure phoneme /ɔ/ do not exist. Instead, words with the /ɔ/ sound exist as an r-colored vowel /ɔr/ as in ‘Florida’ and ‘orange. The /ɔ/ sound also occurs as a diphthong /ɔɪ/, as in “boy” and “noise.”. Words with /ɔr/ can be challenging if we do not know how to pronounce the /ɔ/ sound: e.g., war, warm,  and order. So it is important to know how to pronounce /ɔ/.   


/ɔ/ is a medium-low back vowel. It is also a round vowel, meaning that the lips are rounded when saying /ɔ/. To know how to say /ɔ/, it is useful to compare it with sounds that share some similar mechanics. Compared with another round vowel /u/, the lips are not pushed out as much as /u/ since the tongue for /ɔ/ has to be low. To make the tongue low, mechanically speaking, the jaw has to drop. To know how much the jaw has to drop, compare /ɔ/ with another round vowel /o/. /o/ is a mid-high vowel, and /ɔ/ is a mid-low vowel. By the way, /o/, as a pure phoneme, occurs in Korean and French, but not in standard American English, where it occurs only as a diphthong sound, /oʊ/. Since /o/ is a mid-high vowel, the jaw does not drop, but /ɔ/ is a mid-low vowel so the jaw has to drop significantly.  /ɔ/ is not an /ɔ/ without the jaw dropping. 


 /ɔr/ words

These are words with /ɔr/ sound:

 with “or”: 

boring, corner, foreign, forest, forty, historical, majority, moral, north, orange, origin, priority, short, story, shorter, reporter, supporter, order, border, recorder, core, pore, or, Thor

 with “ar”: 

quarter, war, warrier, warm, swarm 

with “oor”:

door, floor, poor

with “oar”

soar, roar, oar  

with “ore” : 

ore, swore, wore, before, more 

with “our”: 

four, pour (poor, pour and pore are homophones)

/ɑ/ words 

/ɑ/ should be a pretty straightforward sound for non-native speakers since the sound is common in all languages. It is an unrounded, low back vowel sound. The sound is called the short O sound by American teachers since the sound is commonly found in letter O. The letter A can sometimes make a short 'o' sound too though. These are words with the pronunciation of /ɑ/

with "a": 

calm, father, wasp, watch, wash, what, walk, swallow, swap  

with "o": 

body, bother, clock, cost, doctor, follow, got, holiday, hot, involve, job, lot, model, not, possible, probably, problem, shop, stop, top, borrow, sorry, tomorrow

R-colored /ar/ words 

with “ar”

arm, army, art, article, artist, bar, car, card, carpet, charge, charm, chart, dark, department, far, farm, garden, guard, guitar, hard, harm, large, march, mark, market, park, part, partner, party, regard, remark, sharp, smart, star, start, target 

 with “ear,” and “uar”: 

heart, guard 



Due to the cot-caught merger, words that used to be pronounced with /ɔ/ are now pronounced with /ɑ/. Consequently, there are no minimal pairs for /ɔ/ and /ɑ/. So we examine minimal pairs with their r-colored vowels. 

/ɑr, /ɔr/ minimal pairs

far, four

tart, tort

part, port

farm, form

barn, born

hard, hoard

barred bored

cart court

mart, mort

mar, more

impart, import

depart, deport

car, core

/ar/, /ər/ minimal pairs

far, fur

shark, shirk

star, stir

hard, heard

barn, burn

heart, hurt

cart, Kurt

dart, dirt

farm, firm

park, perk

/ɔr/, /ər/ minimal pairs

 

for, fur

store, stir

born, burn

short, shirt

form, firm

warm, worm

war, were

torn, turn

bored, bird

court, Kurt

dork, Dirk

pork, perk

course, curse 

hoard, heard

hoard, herd

former, firmer

accord, occurred

conform, confirm

course, curse

warrier (he who fights), worrier (he who worries)




/ɔr/ vs /ər/ vs /ar/ comparison sentences

Now that we learned /ɔr/, /ər/ and /ar/, we can pronounce the following tricky words confidently: ‘warm’ and ‘worm’. The key is to know that ‘warm’ has /ɔ/ sound, and ‘worm’ has /ə/ sound. 

warm - worm

Today is pretty warm. 

Birds eat worms. 

g


These are comparison sentences with the r-colored vowels, /ɔr/, /ər/ and /ar/.

form - firm - farm

Please fill out the form. 

My decision is firm.

Old McDonald had a farm.


born - burn - barn

It was born in a burnt barn.  


hoard - herd - hard

She hoards old newspapers.

In an elephant herd, the elders walk in front.

It’s hard. 


These are some more r-colored vowel comparison sentences.

Our former boss was a bit firmer when it came to discipline.

It never occurred to me that the U.S. would sign the trade accord.

You have to conform to the rules. If you don't, that will confirm our doubts about you.

A language course should not teach students how to curse.

World wars shouldn’t not happen.

Worriers worry about another World War.

We need warriors, not worriers.

Worms thrive in warm weather.



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