The spelling of the word "ehiogu" is challenging due to its unique pronunciation. The word is pronounced as /eɪhiɒɡuː/ in IPA phonetic transcription, which makes it difficult to spell without prior knowledge. The first syllable is pronounced as "ehi," with a long "e" sound followed by a short "i." The second syllable is pronounced as "ogu" with a long "o" sound and short "u." Overall, the word ehiogu is a good example of how complex English spelling can be.