When to use おう and when to use おー?

Question

I have read that both おう and おー are read as "ō".

When to use each one? Is there a rule for it, or is it totally random?

90 % of the time, you want おう (and こう etc), the rest is おお. おお never happens with an _on_ reading AFAIK. — oals, Feb 24 '16 at 15:01
Yes, おう in [王様]{おうさま} is read as *ō*, but [追]{お}う, [負]{お}う are read as *ou*... no? — Chocolate, Jun 11 '16 at 10:24
The one that surprised me a lot when I first ran into it was 炎（ほのお）. — WeirdlyCheezy, Jun 13 '16 at 17:35

score 0 · Answer 1 · answered Feb 25 '16 at 05:01

0

In Hiragana you would use 「おう」 or 「おお」, in Katakana you would use 「オー」.

All of them can be read as "ō".

For example:

フォーク　(fōku)

おおきい　(ōkii)

こうえん（kōen）

answered Feb 25 '16 at 05:01

1 Answers1