The word "Reveka" is spelled with an "e" after the "v" because the "v" is pronounced as a consonant rather than a vowel. The IPA phonetic transcription of "Reveka" is /ɹəˈvikə/. The "e" after the "v" indicates that a separate syllable follows, rather than it being part of a diphthong. The vowel sound in the first syllable is a schwa /ə/, followed by a long "i" sound /i/ in the second syllable, and ending with a schwa /ə/ in the final syllable.