How do people develop accents? Like someone with an American accent...

[Rachypoo]

...picking up a British accent? I know that it's possible, I've just always wondered how.

My neighbors for instance. They're Italian but spoke with an American accent. They went to Italy for vacation (I don't know how long) but they seemed to have developed Italian accents. This vacation was many years ago and they still have those accents.

How do people develop them and how long does it take? If I were to listen to people with Irish accents often, would I pick up one?

[emiteemergency]

Because theyve gotten used to the way people talk. Like if I went to New Zealand and I came back i would have british-ish accent. Its just something you pick up. After a while back in the U.S. you get used to the u.s. "accent"