african american vernacular english allophone american english british english cockney consonant cluster consonant mutation english compound english orthography fortis and lenis free variation grammatischer wechsel great britain greek language hiberno-english high german consonant shift homer international phonetic alphabet lisp london markedness modern greek non-native pronunciations of english old high german phoneme plato pronunciation proto-germanic proto-indo-european language received pronunciation sandhi science scots language scottish english sibilant consonant spelling pronunciation stop consonant th-alveolarization th-debuccalization th-fronting th-stopping then-thyn split voiced dental fricative voiced dental plosive voiceless dental fricative voiceless dental plosive wales