Sometimes, sounds are lengthened for emphasis. For example, see ["とっても versus
とても"](https://japanese.stackexchange.com/questions/808/%E3%81%A8%E3%81%A3%E3%81%A6%E3%82%82-versus-%E3%81%A8%E3%81%A6%E3%82%82).

What are the rules governing this process?

  * Are there restrictions on where lengthening can be inserted?  
とっても or とてえも or とても～?  
すんごい or すご～い or すごいー?

  * Is it predictable which sound is inserted?  
すんごい rather than す～ごい or すっごい?

I've given examples, but I'm hoping to learn if any general rules exist.
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2012-10-15T10:26:57.590
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2014-12-24T22:44:31.883
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pronunciation phonology spelling spoken-language
Rules for emphasizing by lengthening sounds
In both of the examples you presented, it's the first consonant of the second
syllable (or mora) that is doubled. Sometimes, I also hear dekai as dekkai.
I've also heard verbs like して being pronounced as しって. That too matches the
pattern of CVCV(x)>CVCCV(x).
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2012-10-16T02:13:22.347
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Maybe this is an overgeneralization, but I find this often has to do with
pitch accent. Example:

とても【LHH】

とっても【LLHH】

すごい【LHL】

すんごい【LLHL】

It seems as if inserted sounds, if they exist, all appear on low to high pitch
transitions. Obviously most words do not have these sounds inserted, and often
only very common interjections would use them.

As for why ん is used rather than a っ, try pronouncing すっごい. It's pretty
difficult, and since intervocalic "g" is allophonic with "ng" which sounds
like ん, it is natural for すっごい to turn into すんごい.
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2012-12-06T22:08:56.417
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2014-03-30T07:45:43.600
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The sungoi is most likely due to the Tokyo nasal g accent. In Tokyo,
oftentimes when there is a "g-" sound in the middle of a word, they'll add in
a subtle "n" right before it. They'll probably still write it as sugoi because
that's what they're saying, just with an accent. This i have learned from my
time on WaniKani because one of the people they use for vocab pronunciation
has the tokyo nasal g thing going on and it really confused me until someone
explained it.

For the lengthening, it's pretty easily compared to english. when we want to
emphasize a word, we stress the syllable that already has the most stress on
it. try it with "totally" or "extraordinary." In japanese, they don't really
use strong and soft syllables like we do, but changes in pitch. I'd compare
raising pitch to beginning a strong syllable, so modifications for emphasis go
where pitch increases.

Hope this helped! :)
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2014-11-24T22:14:12.407
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