Yes. See, Australia, New Zealand, Polynesia, Indonesia, Malta, Haiti, Dominican Republic, Cuba, Barbados, Jamaica, Japan, Philippines, and many more.
Indonesia
Yes, it is possible. Greenland is the largest island, and is also a country.
There's Madagascar, Malta, Australia, New Zealand, Japan, Sri Lanka, the UK, and if you want whole archipelagoes there's Indonesia, the Philippines and the Micronesian islands.
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