The spelling of "is one case" follows the standard English alphabet, but the individual sounds can be broken down using IPA phonetic transcription. "Is" is pronounced /ɪz/, with the "i" sound followed by a voiced "z" sound. "One" is pronounced /wʌn/, with a short "u" sound and a silent "e" at the end. "Case" is pronounced /keɪs/, with a diphthong "ei" sound followed by an unvoiced "s" sound. Overall, the spelling of "is one case" accurately represents the sounds of the English language.