Pronunciation of "ou"

[matthewv]

I'm confused about the purpose of the "u" in words like doumo, arigatou, and ohayou. Does it mean that I should pronounce a "u" after the "o" or does it mean that I should merely lengthen the "o"? Or both? Or does it vary depending on the word?

Arigatou gozaimasu.

Edit: Or maybe... is it possible that I need to length the syllable but saying a "u" is optional? I don't know.

[Belton]

You lengthen the o sound.
If every syllable is one beat. ou is two beats. and is oo.
(btw a double constanant like tt in matte means you hold for a beat before the double constant. ma (hold) te. )

It's slightly a problem of writing Japanese in romaji, the hiragana way of writing is followed. Sometimes a macron ( ō ) is used instead which is a bit easier.

In hiragana the rule is
a あ lengths a row of syllables
i い lengthens i row,
u う lengthens u row,
i い lengthens e えrow and
u う lengthens o お row.
(small tsu っ indicates a short pause (glottal stop))
katakana is easier where a dash is used to lengthen a sylable.

It's useful if you can listen while reading. The romaji transcript of the podcasts is available on the MP3s. Then you can see how pronunciation works much more easily than trying to work it out from a written source.

If you can I'd reccommend learning kana, it's much more useful in the long run.