@trying2learn,
Wanhong, this is silly. Seriously. It's important that you understand that English is fluid and anywhere English is spoken it takes on it's own flair. There is no such thing as American English or British English. There is a difference in the spelling of some words in the dictionaries of Oxford or Webster's, the pronunciation will vary depending entirely on where you are in the US, the UK, Australia or other countries or the tiny counties or cities in between.
The only real difference is the slang, or the local sayings.
Basically, don't limit yourself to an ideal. It's doesn't exist.