This is the English that is supposed to be what native speakers use.  But, do not be surprised to find some debate as to what this actually means.  Many early post-war students of English learned British English, while much of the English taught today is supposed to be American English.  Remember the words of George Bernard Shaw... "the United States and Britain are separated by a common language." 

Check out some interesting American and British expressions...  
It is important to remember that even though someone speaks a language quite fluently, chances are they will not understand the colloquial language, which is full of slang, idioms, clichés and other expressions.

Japanese students are required to learn English in school beginning with Jr. High (some begin in elementary school). This means that most Japanese study English for at least six years. Many go on to complete another two or four years at colleges or universities.  However, many Japanese will quickly point out that even though they studied English for ten years, they have difficulty with basic conversation and verbal comprehension.  People visiting Japan for the first time always find this paradox difficult to understand.  There is, however, is a logical explanation.

One problem is the fact that many Japanese teachers of English cannot speak English themselves.  Emphasis is placed on reading, writing, grammar, and rote memorization.   Add to this the fact that during these six to ten years of study most students have limited opportunities to hear correct, or “native” English spoken, and certainly do not have many opportunities to engage in conversation with native speakers on a regular basis..

Another difficulty is that although there are probably thousands of "native speakers" teaching in Japan, many are not properly trained.  For years it has been known that teaching English in Japan can be very lucrative.  Just flip through the English yellow pages, or the classified ads, to see the incredible number of English language schools and ads for English teachers.   

Second - English That Has Become Japanese

Actual words and expressions have been adapted and are usually used in colloquial, less formal Japanese. A word of caution--just because you recognize the word or phrase does not mean you will understand the meaning as the Japanese use it.

Third - Original Japanese-English

This is the English created by the Japanese that does not exist anywhere else in the world. Sometimes even the Japanese do not fully understand these expressions, but will use them anyway because it is fashionable and looks or sounds good.

Now that you have decided not to spend your time and money learning Japanese, you should take a little time to learn the essentials of Japanese pronunciation. Otherwise you may not understand Japanese-English. Most  foreign words and phrases are written in a syllabic script called "katakana", and are pronounced as they are written. This explains why so many Japanese have trouble hearing and understanding correct English pronunciation.   

For example, coffee becomes "koohii," hotel becomes "hoteru." A simple sentence such as "this is my business card" becomes "disu izu mai bijinesu caado."  All Japanese words end in a vowel, and almost without exception, the last syllable is pronounced.  

The Japanese are always mixing up the "L" and the "R", which reminds me of a funny story...

There was a Japanese man living in the US who went to visit his eye doctor.  The doctor told him that he had a cataract.  The patient was confused, thought for a few minutes, and then finally told the doctor that he did not have a cataract.

The doctor repeated his diagnosis, but the Japanese man became insistent.  Finally the patient asked the doctor to step to the window and pointed to the parking lot.  "See, I don't have a cadaracku (Cadillac), I have a rincon konchinentaru (Lincoln Continental)."     

Everyone knows it is like the "L" in Rome, and the "R" in London!!