I have a question about Japanese. Why are some vowels just like not pronounced? Like, “ichi” is spelled like that, but I don’t think I’ve ever heard that second “i” pronounced. Or like “Yusuke” which sounds like “Yoos-kay”, where the second “u” isn’t pronounced. Or “Asuka”.
Are they just like really short vowels (vowel length) and technically are pronounced but my English-speaking ears don’t hear it?
The “traditional” analysis (see, e.g., T.J. Vance, An Introduction to Japanese Phonology, 1987), is that high vowels are devoiced or elided entirely between two voiceless consonants (/p/ /t(s)/ /ch/ /s(h)/ /k/ /h/), or word-finally after affricates and fricatives (/s/ /sh/ /ch/). The apparent motivation for this would be assimilation to the vowel’s surrounding environment – it’s “easier” in some sense to pronounce three voiceless segments in a row than a “voiceless, voiced, voiceless” sequence. There are some differences on the particular phonological feature involved (maybe it’s [spread glottis] instead?), and at least one study argues that this is a probabilistic occurrence rather than a hard-and-fast rule, affected by external circumstances – but that information is likely only of interest if you’re a phonologist.