Native English may cease to be the gold standard.
Most people now learn English to communicate with other nonnative
speakers — and even many of their teachers aren’t native — so they
acquire few expressions and idioms. The linguist Jennifer Jenkins
describes a British TV interviewer asking a perplexed Italian opera
singer whether his trip to England is “going swimmingly.” She writes
that, at European Union conferences, nonnatives who can easily
understand each other’s English switch on their translation headphones
when someone from Britain or Ireland takes the stage. English will mutate. A
recent Irish conference on “World Englishes” included sessions on
“Egyptian English as a new English variety” and “English in the
linguistic landscape of Kazakhstan.” The linguist Marianne Hundt of the
University of Zurich says common errors like “we need to discuss about
this” or “I want some advices” could enter native speech.
Now my experience seems to confirm this. Except in a corollary sense. Growing up my father's first job was a Spanish interpreter for an import/export house in New York. Depression and all it was not bad. So we spoke a bit of Spanish at the dinner table. Then I had many Spanish speaking friends, they were Puerto Rican, and I assumed that Spanish was Spanish. Well I later found out my Spanish was Brooklyn compared to the Queen's English if you go to Madrid! Then Italian. As a kid the best priest to go to for Confession was at the all Italian church, Our Lady of Mt Carmel, and you got off easy if you said your Confession in Italian. Well my Italian was Staten Island street Italian, even though I took a few courses over the years. I tried it in Florence, they thought I was a blue eyed Mafia Don!. Then my French, I know a lot of French, am fluent, as long as I am not in Paris. Spent two weeks in Normandy after 9/11 and spoke only French. When I got back to DeGaulle on my way home they even thought I was Canadian! Compliment, I think.
Now Greek, I am reasonable at that, and yes if you are familiar with medicine then half the words you already know, especially if you have the alphabet down. Russian is a bit harder but I mastered that, yet my teacher was Ukrainian and so I could never pass the spy test!
Now English. Having traveled the world one can survive in English by having 1,000 words, some limited Grammar and off you go. The trick as with any language is pronunciation, English is horrible if not a native, and the idioms.
Also Americans are horrible in speaking to non-Americans. They use sports metaphors and idioms as if everyone knew them. A classic case was a fellow who worked for me once took over a meeting and spent an hour speaking in football metaphors, American football. There was a revolt. He was gone.
English is a powerful language, especially if one keeps on the straight and narrow. No sports metaphors, no jokes, and please, try to get some grammar. All non-native speakers who are moving up have learned grammar. Unfortunately we seem not to teach it any longer!