I have seen slangs are the ultimate way to communicate these days but still I get this sensation it's a way through which people hide their inability to express themselves in a decent English.

I know English is just our lingua franca but we can't deny the important role it has played for us in and out of our country. Is it really right of us to defile it like that with those non English words and grammatical constructions?

Language belongs to the people. Therefore, if the people choose to not use standard/proper English for everyday communication, they are not obligated to. English will remain a/the language for schools, government work, international interactions, etc. Outside of that, they can speak however they want, so long as they can effectively pass their message across.

Well, I have a saying which is "you have to know when to turn it on and off". I use slang often, but mostly in a social environment, or when I'm amongst those who use it also.

When I'm in a professional environment (eg. school, work), I have myself trained not to use any slang.

blackspade:

Well, I have a saying which is "you have to know when to turn it on and off". I use slang often, but mostly in a social environment, or when I'm amongst those who use it also.

When I'm in a professional environment (eg. school, work), I have myself trained not to use any slang.

Says it all.
Speak slang in informal, social environments.
Avoid it in professional environment( school, work etc).

When I was being interviewed by the COO of the company I work now(final stage), I answered 'yeah' to one of her questions and she responded 'Don't say yeah to me again. Yeah is a casual slang'. I apologized. A couple of minutes later, I repeated 'yeah' again, so used to it, and I quickly corrected myself. She didnt even talk this time around. She knew 'this one is so used to it'. That was enough for me to fail the interview, but I scaled through sha.

I find it quite appalling when people who are suppose to know what is up bothers about trivial things like africans perfecting foreign languages,such as english.

English people can't even bother to pronounce correctly african names that are suppose to be written in english alphabets,they don't give a mess,they  think your name is not worth mentioning,just a nuisance that needs help.I wish people know how nasty english people are,you don't  just want to talk like them.

Language like names is the soul of life,it is ones explanation and window into the world,you got to create and speak in a language you don't understand,like delving into the abyss,it opens up.

Foreign language or not, people should know when not to use slangs. Personally I get put off when people speak the wrong way.

That is your opinion based on your horizon and understanding of originality and indoctrination.Language and religion are  great weapons use in destroying people's culture,concepts and self dignity,just like africa today,birds of no feather,no concepts,no opinions,no views,no common sense.