According to my knowledge, there are two big categories of teachers of English: teachers of English who are native speakers of English and teachers of English who are non-native speakers of English. These two categories can be divided into subcategories as well but that is not necessary here. Let’s just consider that teachers from both categories are well educated with a good command of English.
It is well known that teachers of English who are non-native speakers of English make mistakes when using English. Usually, these mistakes are not obvious for learners of English but they are obvious for native speakers of English who can recognize immediately a non-native speaker of English, usually by his accent. Now, the question is how the accent of teachers of English who are non-native speakers of English, affect learners of English and their spoken English.
You might think that the learners copy and reproduce every single mistake made by their teacher. Well, that is not true, at least not in my case. To copy the accent is even more difficult.
Since I am Romanian, I do speak English with a Romanian accent and the sounds I produce when speaking English are similar to those of Romanian language. But, here is the interesting thing; none of my students copied my accent, they still speak English with their own accent, Vietnamese accent.
If I were American for example, could they copy my American accent? Probably not! Everybody watches movies and if reproducing American accent would be easy then everybody could speak English like an American.
Most learners of English watch movies in English language (therefore they listen to English) and watch YouTube videos in English more time than they spend in the classroom listening to my Romanian accent. The accent of a teacher of English who is non-native speaker of English is not transferred to the learners.
Let’s take two examples of two people who speak with me everyday; my wife and my daughter.
My wife is Vietnamese and we have been married since January 2005. Guess what, she still speaks English with Vietnamese accent (just like my students) and her pronunciation is very “Vietnamese”. This is not a singular case! I know at least a hundred cases of Vietnamese girls who married foreigners, native or non-native speakers of English, who speak English just like my wife. A big improvement is in the vocabulary area. She learned a great amount of vocabulary words since we have to talk about a lot of things and situations.
My daughter is more than seven years old now and although she is a Romanian citizen, her mother tongue is Vietnamese since she has been living in Vietnam since she was 6 months old. She speaks Vietnamese at home with her mother and at school, and Romanian and sometimes English with me.
I find her accent, when speaking English, to be much better than mine. That is not only my opinion, it is others too. First of all, she has a great voice (not like mine, my voice is terrible) complemented by the fact that she is a child and a girl. Of course everything she says sounds better than if I would say.
But, why is her accent better than mine since I am the only one who speaks English with her? Well, since she speaks Vietnamese and Romanian very well, two very different languages, she is used to reproduce different kind of sounds, sounds of two languages. That gives her a greater advantage when it comes to reproducing English language sounds.
Although everything she watches on TV or the Internet is English only, it is not always spoken by a native speaker of English which I believe it helps her with listening skills. This, complemented by the fact that she speaks two very different languages besides English, gives her the better accent.
As you can see, the spoken English of two people who speak daily with a non-native speaker of English is not affected by his non-native accent. It is the same case with the learners of English whose spoken English is not affected by their teacher’s non-native speaker accent. Can the accent of these people be changed or influenced by a native speaker of English? I don’t really think so!
Although there are learners of English who greatly improved their accent over time, I personally think that in order to acquire an accent similar to that of a native speaker of English, the learner needs a very strong desire to change his accent, needs many hours every day to be exposed to good examples of English, communicate in English with people willing to correct every single mistake, and probably an expert in accent reduction.