By definition it can't be a continent and an island. If the terms can overlap, then Eurasia is an island.
Why is it "Aûstralio" and not "Aûstralo" ? I don't understand because australians are mostly immigrants who gave it its name... So Australia should be "Aûstralo" and Australian "aûstralano", no ?
Australians live in Australia.
Aŭstralianoj loĝas en Aŭstralio.
(Aŭstrali'an'o'j loĝ'as en Aŭstrali'o.)
Your assumption - that Australia is a "new world" country - is correct,
but you got tricked (or rather: missed an -i- ) on the "what's the root word?" part ...
(the root is Aŭstrali' (see la Plena Ilustrita Vortaro de Esperanto)
There is a country called Australia, or the Commonwealth of Australia, which almost exactly corresponds to a landmass that can be termed mainland Australia, plus the island of Tasmania.
It sits on a continent that is variously described as Australia, Australasia, or Oceania, which comprises the Australian landmass plus some of the surrounding islands such as New Zealand and New Guinea.
The continent of Australia includes New Guinea and various other Oceanic islands, but not New Zealand. NZ belongs to its own sunken continent, Zealandia.
It's a country because it's self ruling, has a government and other political stuff.
from the Tips and notes for the skill Accusative:
The -n ending in Esperanto is called the accusative.
Be aware that the accusative ending -n is never used with the verb estas:
Li estas knabo. (He is a boy.)
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