What makes learning English difficult? a) Is the grammar? b) Is the spelling? c) Is it the tenses? d) Is it pronunciation? e) Is it all the different English accents? d) Is the slang and colloquial or informal expressions? e) Is the lack of cultural understanding? The history behind the words and expressions.Have a look at this link for British colloquial expressions - http://www.lifehack.org/articles/communication/30-awesome-british-slang-terms-you-should-start-using-immediately.htmlAnd this one too - http://www.lifehack.org/articles/lifestyle/simple-british-slangs-you-probably-should-start-using.htmlThis is quite extensive - http://www.effingpot.com/slang.shtml And this too - http://www.peevish.co.uk/slang/