What is the unintelligible Japanese dialect?
Kyushu-ben
Kyushu is the southern and westernmost island of Japan and some of its dialects are totally unintelligible to other Japanese speakers. In addition to changes in vocabulary, Kyushu-ben has some differences in how some of the vowels are pronounced.
Tsugaru Dialect: One of the most difficult dialects in Japan.
The Okinawan languages are related to Japanese, but they are by no means mutually intelligible. Today, almost everyone on mainland Okinawa can speak standard Japanese, though there are regional words and slight grammatical variations particular to Okinawa.
Kansai dialects are intelligible with rest of Japanese speakers. Mondai Arimasen (There is no problem). Some comedians use Kansai dialects on TV but you don't need subtitles to understand them.
Many Japanese speakers have difficulty pronouncing the English consonant sounds /l/,/r/, /f/,/v/ & 'th'. Japanese has only 5 vowel sounds. English has 20. English long & double vowels are often challenging. Word stress is often flatter and more even than an English native speaker.
You can speak standard Japanese (often called 標準語 ,ひょうじゅんご, hyoujungo, which is “standard Japanese,” or 共通語, きょうつうご, kyoutsuugo, the “common language”), and most people will understand you easily.
1. Mandarin. As mentioned before, Mandarin is unanimously considered the most difficult language to master in the world!
Kansai dialects are probably the most famous Japanese dialects of all. It is spoken in the Kansai region, the western part of the main island of Japan including Osaka and Kyoto. They have a very unique accent which is quite different from the standard Japanese.
1. Mandarin Chinese. Interestingly, the hardest language to learn is also the most widely spoken native language in the world. Mandarin Chinese is challenging for a number of reasons.
Dialects from different areas can be so different that they are not mutually intelligible, but most speakers are able to communicate in standard Japanese, which is based on the Tokyo dialect.
What are the three dialects of Japanese?
Misao Tōjō classified mainland Japanese dialects into three groups: Eastern, Western and Kyūshū dialects.
Kansai Ben (関西弁)
It is the most well-known of all non-standard Japanese dialects. Kansai Ben on its own constitutes many variations in different locations where it is spoken.

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