Accent/Language Overview
Japanese accents are, of course, dependent on Japanese language. A quick review of the Japanese language Wikipedia page might be helpful, as might a look at the page for Japanese over on Omniglot.com. Perhaps most different from English is the timing of Japanese. English is a Stress-timed language, whereas Japanese is a Mora-timed language. Morae are similar to English syllables, and each gets essentially equal value in Japanese. So native speaker (NS) of Japanese, when speaking English, tend to apply mora-timing to English, which leads to a distinctively different rhythm and stress feeling. Most notably, certain elements of language, e.g. the /n/ mora, function as a single unit, as do the first element of twinned consonants. So a word like Nippon isn’t just two syllables, it is 4 morae ni-p-po-n.
In Japanese, there are “phonotactic” rules that limit how morae (syllables) can be built. Most of the time they are either vowels, 1 consonant plus a vowel, or occasionally 1 consonant + “y”+a vowel. So you can have syllables like “u” (similar to English oo), “mu” (similar to English moo), or “myu” (similar to the beginning of English music). English Consonant clusters are a significant challenge to Japanese NS who are just learning the language—they tend to add vowels to break the consonants up. So the English loan word in Japanese, such as the word derived from “techno+stress” is tekunosutoresu. Often the /su/ mora gets reduced a little, so that they aren’t all even, but they aren’t full clusters as they are in English.
Examples of Japanese words: C= consonant V=vowel
こ・こ・ろ ko・ko・ro “heart” CV・CV・CV
こ・こ・ろ ge・n・ki “energetic” CV・C・CV
あ・か a・ka “red” V・CV
Stress
Japanese words lack the stressed syllables we’re used to in English. All key words in a sentence primary stress on one syllable, and possibly secondary stress on another, and these are counter-balanced with unstressed syllables. For example, in the word “important”, the stress is on the “port” syllable. In “interesting”, the stress is on the “int” syllable.or this reason, English is called a stress-timed language.
Japanese has long and short morae, but not stressed ones. The familiar word “teriyaki,” a cooking technique where meat is marinated, is pronounced differently in English than in Japanese, and much of the difference is in the stress.
English pronunciation: [ter-ee-YAH-kee] Primary stress on YAH, maybe a secondary stress on ter (depending on how fast/slow or emphatically you’re speaking). Japanese pronunciation: [teh-rih-yah-kee] In Japanese, all of the syllables gets the same amount of stress. In fact, to many English speakers, the syllables that we normally don’t stress feel somewhat over-stressed!
Pitch Accent
Japanese also has pitch patterns within words. This is similar to, but not the same, as the way that pitch is used in Mandarin to differentiate words. While Mandarin has 5 tone contours, Japanese only has two pitches, High and Low, though they can be contrasted in many different combinations. Most Non-Native Speakers (NNS) of Japanese don’t learn proper Pitch Accent; getting this right is extremely challenging. Incorrect pitch accent is the leading indicator that someone is a NNS. As far as accented English goes, pitch accent has very little implication for your accent, though it is possible that Japanese speakers may have a flatter, or broader sentence intonation pattern in English than we are familiar with. Also, some Japanese speakers use high rising terminals (aka “uptalk”), and so sound like they are asking questions when they are not.
Vowel Differences between English and Japanese
In Japanese, there are 5 vowels: a i u e o (which conveniently map onto the 5 latin letter shapes for vowels, so these are used in the Japanese writing style know as rōmaji). Most Japanese speakers of English will use the equivalent of these 5 vowels in place of English vowels and diphthongs whenever they can. More successful English speakers adopt more English sounding vowels, less successful ones stick to the Japanese vowels. Let’s look at each of these 5 vowels separately.
a: あ IPA [a] North American English doesn’t often have this vowel in isolation—most frequently it’s the first element of the diphthong in PRICE [aɪ].
i: い IPA [i] This is the vowel in FLEECE. Perhaps the most consistent vowel in the world’s languages!
u: う IPA [ɯ] (The IPA symbol looks like an upside-down m, but it’s really an /u/ with an extra “bowl”. This is similar to English “oo”, except it is compressed, with no lip rounding.
e: え IPA [e] This vowel is similar to the beginning of the FACE diphthong; it’s tighter than the /ɛ/ vowel in DRESS.
o: お IPA [ɔ] This is similar to the beginning of diphthong in CHOICE, or to a British “aw” vowel in words like THOUGHT. Though it is written with an “o” it is more open than the English version of such a vowel.
English diphthongs, like the PRICE diphthong are built out of short vowels paired together in Japanese, with the two elements pretty equa,l whereas in English the first element is significantly longer and more stressed). So Ice Cream is a loan word and it comes out aisukuri-mu.
Consonant Differences between English and Japanese
The Japanese alphabet has a relatively small set of 17 consonants [m, n, ŋ, p, b, t, d, k, g, h, s, z, ʃ, r, j, w, ɸ] . English on the other hand has at least 25 consonants [m, n, ŋ, p, b, t, d, k, g, h, θ, ð, f, v, s, z, ʃ, ʒ, tʃ, dʒ, r, l, ɫ, j, w ]
Generally speaking, the articulation placement for consonants should feel a little different for North American English speakers. So many of our consonants are articulated with the front edge of the tongue on the alveolar gum ridge behind the upper front teeth: /l. n, t, d/ touch this spot, and /r, s, z/ come very close. In Japanese, these sounds are generally said with a slightly different point of articulation: further back on the “blade” of the tongue (so it’s a so-called laminal articulation) so that the front edge of the tongue can stay down behind the lower front teeth. If these sounds are before the vowel /i/, they will be more laminal, while should they be before the vowel /u/ they are much more likely to be retracted.
Perhaps the most challenging sound for Japanese speakers to master in English is the /r/ sound. Japanese does have an /r/ sound, but it is very different from a North American one. More like a /d/ or very brief tapped /r/ (IPA [ɾ]), which we might hear in an archaic British accent in a word like very. This consonant tap substitutes also for the consonant /l/, which Japanese lacks altogether. Even skilled L2 English speakers may struggle with their /l/ and /r/ sounds.
Japanese differs from our /w/ consonant, so it uses its “u” vowel (IPA [ɯ]), which is compressed and not rounded.