Is it known why a さかや normally has a か, rather than a け like in さけ?
Are there many other -や constructions for stores that change the spelling of the word added to?
(Especially in the ancient times,) there were/are bound morphemes (morphemes that cannot be used in isolation as a word) that end with the vowel
When they are used as the first component of a compound noun, the
These morphemes cannot be used in isolation, but there were ways to modify them so that they can be used by themselves. One such way was to attach the vowel
These forms derived in this way are called 被覆形.
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