I think they are from Australia. 我想他们是澳大利亚人。

A: What about that group? They're speaking English, aren't they?

A: 那群人呢？他们在说英语，是吗？

B: Yes. Let me try and listen to the accents.

B: 是的。让我来听听他们的口音。

A: British? American? What do you think?

A: 英国人？还是美国人？你怎么看？

B: No either. They're not British or American. I think they're from Australia or New Zealand.

B: 都不是。他们既不是英国 人也不是美国人。我想他们是澳大利亚人或者是新西兰人。