Does it matter whether you drop vowels in spoken Japanese?

Question

(This question started as a dual question about when to drop vowels and whether it matters. The first question is well answered at What are the rules regarding "mute vowels" ("u" after "s" and "i" after "sh")?.)

I'm just starting to learn Japanese, and one thing I've noticed is that vowel sounds--in particular, i and u--are often dropped by Japanese speakers. For example, "suki" is usually pronounced like the English word "ski", "desu" usually has the final "u" dropped, and I sometimes--but not always--hear "ichi" pronounced without the final "i" sound.

My question is: how much does it matter whether you drop vowel sounds or not? Will native speakers notice either way?

Answer 1

I think I can speak to this because I used to have (maybe still do) trouble getting vowel pronunciation right, and have struggled a lot with it.

Japanese may have situations when they drop vowels, such as the ones you name.

This is not an indication that it's simply generally applicable, though. There is a feel to when it is right that is the kind of thing a native speaker can do without knowing any particular rule.

As a non-native speaker, though, it's harder to plug into what that rhythm is, and when it's right and when it's wrong to do so.

For me personally, one of my main issues is that I have some trouble with two vowel sounds in a row, such as 青{あお}い (blue). In the English accent that I speak natively, the tendency is to compress vowel sounds. So, before much deliberation and practice, I would pronounce 青{あお}い as a two syllable "ow-ii" (something like that, not sure how to spell phonetics). Japanese speakers would not understand me.

In summary, to answer your question, yes, it does matter a lot whether or not you drop a vowel sound, and you will in fact very likely be not understood if you drop, or change, a vowel sound. Native speakers definitely do notice.

My recommendation is to try and emulate pronunciation of all vowel sounds as clearly accurately as you can for now, and then slowly introduce dropped sounds and other variations by copying them as you hear them on a case by case basis.

Answer 2

First of all, muting wrong vowels can make a speech hard to understand. For example, if a speaker pronounces さくら with the first /a/ omitted or devoiced, the word can become unrecognizable depending on the context.

On the other hand, I think that vowel muting is optional for comprehension; that is, not muting the vowels that can be muted does not affect whether a speech is understandable or not. I guess that most people do not even notice the difference between a speech with vowel muting and a speech without vowel muting, as long as one does not mute wrong vowels.

Note that vowel muting is a feature of some dialects of Japanese including the Tokyo dialect (on which the “standard” dialect is based). I think that some of the speakers of the dialects without vowel muting do not mute vowels even when they speak the “standard” dialect.