I know there are many differences between British English and American English.

I am a Korean. There are native English teachers from the U.S., England, Australia and other English speaking countries.

I am not sure which English we are learning. It could be mixed..

so I wonder when you read an English article which non-English speaker wrote using both American English and British English together, how you would think about it? Is it going to look funny to native English speaker? or You (native English speaker) also

sometimes use both American and Birtish English on a article?

As an online teacher of English this question comes up quite a bit. There are in fact quite a few differences between British and American English only they are not as apparent since they are both 'English'. I will give you a few examples which I explain to my students:

  1. have you got? (British) do you have? (American)
  2. on the week end (American,Canadian) at the weekend (British)
  3. outght not (strictly British) should not (typically American, Canadian)


Steve-Online English Teacher

Aside from some small spelling variations, there are virtually no differences in the written language.
Students: Are you brave enough to let our tutors analyse your pronunciation?
It wouldn't be a big deal to mix vocabulary. It would resemble writing that has slang in it. There are a few words that can be confused (like football or chip) but the writing would generally be clear.
 anonymous's reply was promoted to an answer.