Mariah rhymes with the word pariah. (You can listen to the pronunciation of pariah at a number of online dictionaries. Try listening to the M-W recording.)
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By the way, I also want to ask if any of you know any sites where we can listen to pronunciation of proper nouns like names of nations, persons, organizations,etc
Many of the online dictionaries also provide the pronunciations of proper names. You can find a wide variety of recordings – names as varied as John, Vietnam, Schuylkill and Nike, for example, can all be found in online dictionaries.
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I can’t really give you a rhyming English word for ‘Coelho’ because that is a Brazilian name. Maybe a good approximation would be this:
Co - ale - yo
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