1. The Similarities and Differences between English and Japanese vowel and consonantal system 2.1. Similarities and Differences in Vowel System
Vowels are the sounds in the production of which none of the articulators come very close together so the passage of air-stream is relatively unobstructed and the air can get out freely. Vowels are the type of sounds that depend mainly on the variations in the position of the tongue. They are normally voiced.
Both English and Japanese vowels can be classified according to three variables: * Tongue height * Part of the tongue which is raised * Degree of lip rounding.
Comparing the Japanese vowel system with that of English reveals some significant differences in the following two areas: * The number of vowels * Tense/lax distinctions.
Charts below indicate the English and Japanese vowel system. i: u: ɪ ʊ ə e ɜ ɔ: æ ʌ ɒ ɑ: Figure 1: English vowel Chart

Figure 2: Japanese vowel Chart
The number of vowels:
As shown through 2 charts, in the English vowel system, there are 13 different vowels identified. Besides, English vowel system includes several diphthongs such as /a ʊ /, /a ɪ /, and /o ɪ /. On the other hand, Japanese has only 5 vowels in its vowel inventory. It is shown that the number of vowels that can be identified in English and Japanese can differ depending on different analysis of linguists or phoneticians, but obviously, there are considerably more vowels in English than in Japanese.
In English, there are five front vowels, /i:/ / ɪ / /e/ /ε/ /æ/ and five back vowels /u:/ / ʊ / / ɔ:/ / ɒ / / ɑ:/, while in Japanese there are only two vowels /i:/ /e/ made in the front and two vowels /U/ /o/ in the back. In addition, the English central vowels /Λ/ /Ə/ do not exist in the five vowel system of Japanese. It is shown clearly in 2 models below.

Figure 3: Front Vowels Figure 4: Back Vowels

Lax and tense vowels: The distinction between lax and tense vowels in either of the two systems makes typically differences between the English vowel system and the Japanese vowel system. The differentiation between tense and lax vowels is made according to how much muscle tension or movement in the mouth is involved in producing vowels. Thus, vowels produced with extra muscle tension are called tense, and vowels produced without that much tension are called lax vowels. “Tense vowel” is also called “long vowel” and “lax vowel” is also called “short vowel”.
As shown in chart 1 and 2, the tense/lax vowels pairs of English such as /i/ vs. /I/, /e/ vs. /ε /, /u/ vs. / ʊ /, do not exist in the five-vowel system of Japanese as there is no tense/lax differentiation. However, it should be noted that although long vowels of Japanese are sometimes analyzed as having the same quality as English tense vowels, this claim is difficult to support, because those vowels of Japanese are not always contrastive in nature as the English tense/lax vowel pairs.
For example, /i/ as in English /it/ “eat” is categorized as a tense vowel as the lips are spread (muscular tension in the mouth) and the tongue moves toward the root of the mouth. On the other hand, /I/ as in English “it” is considered to be a lax vowel as there is little movement of the tongue or muscular tension of the lips involved in its production, compared to the manner in which the tense vowel /i/ as in ”eat” is produced.
Another feature quite interesting is that vowels in Japanese can independently make meaningful words. For example, "house" in Japanese is “ie”. The word for "no" is “iie”. Said at natural speed, the "ee" in “iie” should sound about twice as long as the "ee" in “ie”. But English vowels need to combine with consonants to make words. 1.2 Similarities and Differences in Consonantal System
Consonant sounds are defined as the sounds in the production of which two articulators come together so that the airstream is obstructed and can not get out freely.
Both English and Japanese consonants are classified according to three criteria: * Place of articulation * Manner of articulation * Voicing
The tables below indicate the English and Japanese consonantal systems according to three criteria above.
Table 1: Japanese Consonantal System | Bilabial | Alveolar | PalatoAlveolar | Palatal | Velar | Glottal | Plosive | + b- p | + d- t | | | + g- k | | Fricative | - ɸ | + z- s | + ʒ - ʃ | - ç | | - h | Affricate | | | + dʒ - tʃ | | | | Nasal | + m | + n | | | + ŋ | | Lateral | | | | | | | Approximent | + w | + ɾ | | + j | | |

Table 2: English Consonantal System | Bilabial | Labialdental | Dental | Alveolar | Palatoalveolar | Palatal | Velar | Glottal | Plosive | + b- p | | | + d- t | | | + g- k | | Fricative | | + v- f | + ð- θ | + z- s | + ʒ- ʃ | | | - h | Affricate | | | | | + dʒ- tʃ | | | | Nasal | + m | | | + n | | | + ŋ | | Lateral | | | | + l | | | | | Approximants | + w | | | | + r | + j | | |

As it is clearly shown in the two tables, English has more consonants than Japanese. There are 24 consonants in English; while there are only 12 consonants in Japanese. The Japanese consonants are the ones not shaded or highlighted, which is b, p, m, t, d, z, s, n, ɾ, g, k, h. The symbols in shaded cells are allophones of Japanese consonants, and the highlighted symbols are semi-vowels. However, to be able to pronounce the complete Japanese alphabet these sounds are needed and these sounds are similar to English consonants; therefore, this part will compare all these sounds together.
Beside the difference in number of consonants, English and Japanese are different in these two aspects: the existence of some consonants (allophones) and the diverse pronunciation ways of the similar consonant.
The first aspect is that there are some consonants (allophones) exist in one language but not in the other. Firstly, English has labiodental and dental sounds, which is “v, f, ð, θ”. However, in Japanese consonantal table, these two columns are completely missing; there is no sound in Japanese categorized as labiodental and dental. Secondly, Japanese has the bilabial, fricative, voiceless allophone “ɸ” which can be pronounced in the word “fujisan” (Fuji Mountain in English). Thirdly, the allophone “ç”, which is sorted as palatal, fricative, voiceless sound, can only be find in Japanese not in English. This allophone is in the syllable “hi” as in “hito” (people in English). The final difference in this aspect, which may be the most important one between these two languages, is “l” and “r” in English versus “ɾ” in Japanese. The alveolar, approximant, voiced sound “ɾ” is written as “r” in the Roman alphabet, but it does not pronounce as the “r” in English. It is considered to be between the alveolar, lateral, voiced sound /l/ and the plato-alveolar, approximant, voiced sound /r/. The three pictures below show how each sound are produced. /l/ is produced with the tongue touches the alveolar ridge, /ɾ/ with the tongue barely taps the alveolar ridge, and /r/ with the tongue do not touch anything.

Figure 5: /l/ in English

Figure 6: /ɾ/ in Japanese Figure 7: /r/ in English
The second aspect is that the consonant “w” in English and semi-vowel “w” in Japanese are not totally the same sound. In English, /w/ is pronounced with lips forward and rounded. However, in order to produce Japanese /w/, the lips are not rounded; instead, the lips are compressed. These two pictures will show the difference more clearly.

Figure 8: /w/ in Japanese

Figure 9: /w/ in English
Other than those differences mentioned above, the consonantal system in Japanese and English are quite similar. As the two tables illustrate very clearly, many consonants are classified and pronounced in the same ways in both languages.
All in all, most consonants are the same in Japanese and English; however there are still some differences in the number of consonants, the existence of some consonants, and the ways similar consonant is formed. 2. Difficulties of Japanese when pronouncing English
2.1. Vowels
The Japanese often have troubles pronouncing English vowels because of the lack of vowels and tense/lax distribution. When you hear Japanese pronounce the partially similar or totally different sounds, it’s difficult to understand because you are used to hearing and making right sounds. It is important therefore, to make yourself aware of how vowels are pronounced by Japanese to make the conversation between the Japanese and Vietnamese effective through English. First of all, the tense/lax distinctions are made in English, which contributes to creating the wider variety of vowels of English, seem to be one of the most problematic areas in pronunciation for Japanese students. For example, Japanese learners often produce the tense/lax vowel pairs of English almost identically as if they were the same vowels; for example, words such as “sleep”, “taste” and “stewed” may be pronounced in the same way as such words as “slip”, “test”, and “stood” are pronounced respectively. Thus, it is quite conceivable that such failure to distinguish between tense and lax vowel pairs of English can cause misunderstandings or miscommunications when we communicate with Japanese speaking English. Furthermore, the Japanese lack of a mid-central vowel / Λ / and a low front vowel / æ / as present in English and the different tongue positioning of the vowel /a/ between the two languages (i.e., /a/ is a low back vowel in English, while it is a low central vowel in Japanese) can bring about a great confusion to Japanese students in producing such words as “hut”, “hat”, and “hot”, or “putt”, “pat”, and “pot”. That is, Japanese students might end up producing these three vowel sounds in such a similar or interchangeable manner that a native English speaker cannot tell which words they are trying to say. For details, analogies below show common pronunciation problems for Japanese learners of English. * Kitao (1995) states that standard Japanese has no diphthongs. He explains further that as Japanese is a syllabic language, there is a clear change between the two vowels, but English diphthongs form one syllable, and the tongue glides smoothly between them. Even though Japanese has similar sounds which consist of two vowels /a/,/u/, they cannot pronounce rightly. * Lifting their tongue high inside their mouths makes Japanese unable to pronounce vowel /eɪ/ ending with the consonant /j/. Therefore, this vowel is often substituted for long /e/. * Vowel /oʊ/ requires the addition of the addition /W/ at the end of it, which Japanese are unable to do. Therefore, the vowel /oʊ/ is often substituted by /ɔː/ * Since the duration of English vowels is affected by the voicing of the following vowel, this may affect the assimilation of English /i/ and /i:/ to Japanese categories. In particular, English /i/ before a voiced consonant will tend to be long enough to be assimilated to Japanese long /I:/, but English /i/ before a voiceless consonant and /i:/ before either a voiced or voiceless consonant will tend to be short enough to be assimilated to Japanese /i:/. They find difficulty in elevating the tongue and holding it close to the roof of the mouth. Therefore, the vowel in some words like: tea, hit, mid is pronounced the same without long or short /i/. * Many Japanese learner pronounce the sound /ɝ/ wrongly in some words such as : hurt, curly, dirty…because in Japanese, there is no /ɝ/. Japanese often pronounce /ɝ/ as either /ɑː/ or /ɔː/. The reason is that they often use the wrong position of tongue and jaw during the utterance of that vowel. Opening their mouths too wide and lowering their tongues make them difficult to pronounce this sound. * With some words like: dad, bad…., the Japanese often pronounce the vowel /ɑː/ or /e/ for /ӕ/. Japanese are not aware of the difference between /e/ and /ӕ/. They don’t stretch or lengthen the vowel /e/, which leads to wrong pronunciation. * If the Japanese are asked to pronounce the vowel in the word /month/, they will pronounce vowel / Λ / correctly, but when asked to pronounce [last month], then they will probably pronounce as /ӕ/ or /e/. They tend to replace this sound with /e/ when it succeeds or precedes either of these vowels. It should be centered inside the mouth while they put the tongue brought to the front and lowered down. * To schwa sound, many Vietnamese cannot understand what word they are saying because Japanese often substitute this vowel for /ʌ/, /ɔ/, /e/. Some of them also the Japanese sound [u] or [o] or even /ə/ between consonants. * As mentioned above, English vowel system has more vowels than Japanese vowel system. That can pose problems for Japanese speaking English. Because vowel distinctions are made by the change of tongue positioning between the five front vowels and the five back vowels of English and Japanese are accustomed to making only two distinctions on tongue positioning in the front and back of the mouth (Japanese vowel system has only 5 vowels). It is clear that understanding Japanese mistakes speaking English vowels assists Vietnamese to not only avoid miscommunications but also correct their mistakes.
2.2. Consonant
As there are certain dissimilarities between English consonants and Japanese consonants, the Japanese usually have difficulties pronouncing words that contain those different consonants. So, Vietnamese when listening to their English can have knowledge to understand what they are conveying. Usually, there are 9 error types happened between Japanese and English: /n/, /r/, /l/, /f/-/v/, /w/, /j/, /θ/-/ð/, /z/, /ʃ/-/ʒ/ and /tʃ/-/ʤ/
The first error type happens with /n/
This error occurs with word ending with [n] in Japanese, which is regarded similar to the English /ŋ/ [ng]. The tongue blade does not come into contact with the alveolar ridge. However, despite the correct movement of the tongue blade, the ending of the word continues to sound erroneous. It is because the Japanese learners usually nasalize the vowel before consonant /n/ retracting the tongue dorsum towards the back of the hard palate as English speakers would do for English consonant /ŋ/.
We can easily recognize this error in these examples: One; Ran; fan; pen; mission; win, etc.
The second error type is: /r/
The Japanese have difficulties in pronouncing this sound because Japanese do not have the sound /r/. So it is hard for them to produce the sound /r/, especially at the beginning of the word such as Rat; right; really .This /r/ sound requires move their lips forward while curling the tip of their tongue back inside their mouths while in Japanese they have to curl the tip of the tongue backwards, position it in the center and move it up and down while preventing it from touching the roof of the mouth . For Japanese, performing those two movements simultaneously seems to be extremely difficult. Therefore, this /r/ is usually replaced by its similar sound /l/. For instance, with the word “right” the Japanese may pronounce as “light”. Knowing that, we will not be confused about what they want to tell us.
With the third error type 3: /l/
With words such as Like; laugh; light; certainly; definitely; available and so on, the Japanese does not have difficulties in realize the position of the tip of the tounge behind their upper teeth. Meanwhile, it is difficult for them to control the movement of their lips during the production of the consonant /l/
Error Type 4: /f/-/v/
These consonant sounds /f/ and /v/ do not exist in the Japanese language. when producing the consonant /f/, Japanese learners are not able to: restrict the downward movement of the upper lip and situate their lower lip underneath their upper teeth to produce the restricted air coming out from the gap between the lower lip and the upper teeth. Sometimes, the consonant /f/ is replaced with the consonant /h/ especially before vowels /u/ and /oʊ/ which require rounded lips. Words illustrate this error the Japanese make are First;Fight; forward; furnished; friend; enough; laugh; tough; cough
Error Type 5: /w/
This consonant /w/ exists in the Japanese language; however, it’s not performed in exactly the same manner as in English. Japanese seem to have no problem producing this consonant before most vowels except /ʊ/, /uː/, /iː/ and /ɪ/. When followed by vowel /ʊ/, /w/ is completely omitted, but when followed by vowels /iː/ or /ɪ/, sometimes /w/ is substituted by /v/ (although they’re unaware it’s /v/). The word “would” is the best example of how this error is displayed. This causes a major obstacle for Japanese learners mainly in connected speech as they’re not able to use /w/ to connect a word ending with the vowel /uː/ or /ʊ/ with another word starting with any other vowel as per the examples.
Some more example are wicked; with; women; do (w)I; situated; situation; casual
Error Type 6: /j/
This consonant /j/ exists in Japanese but never precedes the vowels /ɪ/ or /iː/ for example Need; read; treat; believe. As a result, it is omitted once it precedes /ɪ/, /iː/, and at times, /e/. Like /w/, /j/ also makes it extremely difficult for Japanese learners to connect the words ending with vowel /iː/ or /aɪ/ with another word starting with any vowel.
For example: Knit; rid; tit; live; mitt; will; sit etc.
Error Type 7:/θ/-/ð/
These 2 consonants do not exist in Japanese. So when pronouncing words contain these consonants like think; both; father, that; mother; weather,… they usually substitute the consonant /θ by /s/ and the consonant /ð/ by /d/.
Error Type 8: /z/
With words contain consonant /z/ such as rise; vegetables; tables; chairs; wise; zebra; zero; reservation,… they usually make errors because Japanese does not have this consonant and it is not specifically uttered in the same way. When this consonant occurs at the end of the word, Japanese speakers always substitute with the consonant /s/. When it occurs either in the beginning or middle of the word, it is preceded by a consonant similar or identical to /d/. To produce this sound, the tip of the tongue makes contact with the teeth prior to releasing the restricted air of the English /z/.
Error Type 9: /ʃ/-/ʒ/ and /tʃ/-/ʤ/
The last error type that the Japanese meet when pronouncing English words is /ʃ/-/ʒ/ and /tʃ/-/ʤ/. Aswith Japanese, /ʤ/ is never pronounced at the end of the word. Therefore, they usually replace this consonant with /dz/, /ʒ/ /tʃ/ or even /ʃ/ for example manage; cage; change; grudge… Besides, the Japanese also add a schwa sound or /i/ after /ʤ/ when they successfully produce it. 3. Solutions to help Japanese to pronounce English better
One purpose of this report is to provide the Vietnamese some methods to help the Japanese improving their English vowels and consonants because if the Japanese could use better English, it will facilitate the communication through English between Japanese and Vietnamese. To emphasize, this section is going to deals with the solutions for the Japanese to pronounce English vowels and consonants more correctly and how they could change their habit of pronouncing English syllables in Japanese way.
The first step in this process is giving Japanese students an overall description of English manner and place of articulation. However, due to the lack of several English consonants and vowels, many Japanese learns often mispronounce those sounds or pronounce them in an unnatural manner; hence, giving the tongue, jaw and lips some exercise before practicing is necessary. For instance, it would be easier for Japanese students to pronounce consonants /l/ if they practice controlling their lips and prevent them from pushing forward a bit. Similarly, the sound /r/ might be uttered out more naturally if Japanese students practicing curling their tongues backwards without touching the roof of the mouth on a regular basis. It would be less difficult for them to produce the sound /i:/ once they find elevating tongue and hold it close to the mouth roof easy. Opening and closing mouth repeatedly every day can also help the Japanese possess a more active jaw movement, which leads to a better pronunciation.
As mentioned in the previous sections, the Japanese have to cope with many difficulties when pronouncing English vowels and consonants. Besides, in Japanese, all the words end with vowels, not consonants as in English, that means when pronouncing English words end with consonants, the Japanese usually have the tendency to add a vowel after them. /i/ is added to words with final consonants /ʧ/, /ʤ/; /u/ appears after /l/, /k/, /g/, /p/, /b/, /f/, /v/, /z/, /ʃ/, /m/, /θ/; and /o/ is after /t/, /d/. Thus, to dismiss this habit, Japanese students should be aware of the existence of final consonants in English words, after that stop replacing them with familiar vowels. For example, the words “catch” and “dodge” will be changed into “catchy” and ”dodgy” in Japanese way. But if Japanese students realize that “catchy” and “dodgy” are two different words, they might soon rectify each word and gradually pronounce English words correctly.
Indeed, there are many useful advice we could give Japanese students to improve their pronunciation. Nevertheless, it is the Japanese students’ task to perceive the differences between English and Japanese consonants and vowels as well as take full advantage of the similarities between these two languages to make them sound more understandable for listeners and communicate more effectively.
References

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Barry Kavanagh. (2007). The phonemes of Japanese and English – A contrastive analysis study
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