Editing Classical Japanese (section)

==== {{nihongo|H-Row|ハ行|ha-gyō}} rule ====

* Some morpheme-medial sounds currently written as {{nihongo2|わ/ワ}}, {{nihongo2|い/イ}}, {{nihongo2|う/ウ}}, {{nihongo2|え/エ}}, and {{nihongo2|お/オ}} (''wa'', ''i'', ''u'', ''e'', and ''o'') were written as {{nihongo2|は/ハ}}, {{nihongo2|ひ/ヒ}}, {{nihongo2|ふ/フ}}, {{nihongo2|へ/ヘ}}, and {{nihongo2|ほ/ホ}} (''ha'', ''hi'', ''fu'', ''he'', and ''ho''), respectively. This is because these sounds (as well as all sounds still written with {{nihongo2|は/ハ}}, {{nihongo2|ひ/ヒ}}, {{nihongo2|ふ/フ}}, {{nihongo2|へ/ヘ}}, and {{nihongo2|ほ/ホ}}) originally had initial consonant {{IPA|/p/}} in [[Old Japanese]], which then changed to {{IPA|/ɸ/}} in Early Middle Japanese, and then, in [[Late Middle Japanese]], split into one of five different phonemes depending on whether it occurred morpheme-initially or morpheme-medially, and then further depending on the following vowel. Morpheme-initially and before {{IPA|/a/}}, {{IPA|/e/}}, or {{IPA|/o/}}, it became {{IPA|/h/}}; before {{IPA|/i/}}, it became {{IPA|/ç/}}; and before {{IPA|/u/}}, it became {{IPA|/ɸ/}}; these three sounds are still written with {{nihongo2|は/ハ}}, {{nihongo2|ひ/ヒ}}, {{nihongo2|ふ/フ}}, {{nihongo2|へ/ヘ}}, and {{nihongo2|ほ/ホ}}. Morpheme-medially and before {{IPA|/a/}}, {{IPA|/i/}}, {{IPA|/e/}}, or {{IPA|/o/}}, it became {{IPA|/w/}}; before {{IPA|/u/}}, it lost its consonant. Finally, later on in the same period of the language the initial {{IPA|/w/}} was lost in all instances before {{IPA|/i/}}, {{IPA|/e/}}, and {{IPA|/o/}} (note that {{IPA|*/wu/}} never existed), leaving the current morpheme-medial pronunciations of {{IPA|/wa/}}, {{IPA|/i/}}, {{IPA|/u/}}, {{IPA|/e/}}, and {{IPA|/o/}}, but the spellings of {{IPA|/ha/}}, {{IPA|/hi/}}, {{IPA|/fu/}}, {{IPA|/he/}}, and {{IPA|/ho/}} (which, in this context, are probably better thought of as {{IPA|/pa/}}, {{IPA|/pi/}}, {{IPA|/pu/}}, {{IPA|/pe/}}, and {{IPA|/po/}}; or {{IPA|/fa/}}, {{IPA|/fi/}}, {{IPA|/fu/}}, {{IPA|/fe/}}, and {{IPA|/fo/}}). This rule primarily applies to native Japanese morphemes, although it is crucial to the mechanics of the long vowel rule that applies primarily to [[Sino-Japanese vocabulary|Sino-Japanese words]], which is elaborated upon below. The modern usage of {{nihongo2|は}} (''ha'') and {{nihongo2|へ}} (''he'') to represent grammatical particles pronounced as if written {{nihongo2|わ}} (''wa'') and {{nihongo2|え}} (''e''), respectively, is a holdover from this rule.

Some examples follow (old spellings are on the left, new spellings on the right; kana in parentheses represent the pronunciation of the preceding character):<ref>{{Cite web |title=ほのおとは何？ わかりやすく解説 Weblio辞書 |url=https://www.weblio.jp/content/%E3%81%BB%E3%81%AE%E3%81%8A |access-date=2022-06-11 |website=www.weblio.jp}}</ref><ref>{{Cite web |title=「仕合(しあわせ)」の意味や使い方 わかりやすく解説 Weblio辞書 |url=https://www.weblio.jp/content/%E4%BB%95%E5%90%88 |access-date=2022-06-11 |website=www.weblio.jp}}</ref><ref>{{Cite web |title=仕合はせの意味 – 古文辞書 – Weblio古語辞典 |url=https://kobun.weblio.jp/content/%E4%BB%95%E5%90%88%E3%81%AF%E3%81%9B |access-date=2022-06-11 |website=kobun.weblio.jp}}</ref><ref>{{Cite web |title=穂の意味 – 古文辞書 – Weblio古語辞典 |url=https://kobun.weblio.jp/content/%E7%A9%82 |access-date=2022-06-11 |website=kobun.weblio.jp}}</ref>
{{fs interlinear|indent=3|{幸せ (しあ'''は'''せ)} → {幸せ (しあ'''わ'''せ)}|shia'''ha'''se → shia'''wa'''se|c2= "happiness"|}}
{{fs interlinear|indent=3|{小さし (ち'''ひ'''さし)} → {小さい (ち'''い'''さい)}|chi'''hi'''sa-shi → chi'''i'''sa-i|c2="small" (the ''-shi'' ending is the classical conclusive form of modern {{nihongo2|小さい (ちいさい)}} ''chiisa-i'')|}}
{{fs interlinear|indent=3|{合'''ふ''' (あ'''ふ''')} → {合'''う''' (あ'''う''')}|a'''f-u''' → a-'''u'''|c2= "come together" (note that every quadrigrade verb that currently ends in {{nihongo2|う}} ''u'' once ended in {{nihongo2|ふ}} ''fu'')|}}
{{fs interlinear|indent=3|{前 (ま'''へ''')} → {前 (ま'''え''')}|ma'''he''' → ma'''e'''|c2= "front"|}}
{{fs interlinear|indent=3|{炎 (ほの'''ほ''')} → {炎 (ほの'''お''')}|hono'''ho''' → hon'''ō'''|c2= "flame"|}}

There are some exceptions to this sound change, although they are rare. They include {{nihongo2|母 (は'''は''')}} (''ha'''ha''''' "mother", expected form {{nihongo2|は'''わ'''}} ''ha'''wa'''''), {{nihongo2|頬 (ほ'''ほ''')}} (''ho'''ho''''' "cheek", expected form {{nihongo2|ほ'''お'''}} ''h'''ō'''''), {{nihongo2|家鴨 (あ'''ひ'''る)}} (''a'''hi'''ru'' "domestic duck", expected form {{nihongo2|あ'''い'''る}} ''a'''i'''ru''), and {{nihongo2|溢れる (あ'''ふ'''れる)}} (''a'''fu'''re-ru'' "overflow", expected form {{nihongo2|あ'''お'''れる}} ''a'''o'''re-ru'' or {{nihongo2|お'''う'''れる}} '''''ō'''re-ru''. Sometimes, as in the case of the first two exceptions, the sound change form exists, usually with a slightly different meaning ({{nihongo2|はわ}} ''hawa'' is a hyper-formal and very respectful term for mother) or is used in different contexts ({{nihongo2|ほお}} ''hō'' is generally used in isolation, while {{nihongo2|ほほ}} ''hoho'' is generally used in compounds). In other cases, as is true of the second two exceptions, the unchanged form is the only one that exists. In addition to these exceptions, some dialects may preserve these sounds as they were at any stage of the language.