The island is encircled by a coral reef.

这个岛周围都是珊瑚礁。

《牛津词典》

It was unknown if the coral base of the island, about 12 square miles, might be subsiding.

至于岛上的约12平方公里珊瑚礁岛是否会下沉，目前还不知道。

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I was heading for Aitutaki, which, with its palm-fringed coral lagoon, is the archetypal tropical island.

我飞往艾图塔基岛(aitutaki)，这是一个典型的热带岛屿，岛上的珊瑚礁泻湖被棕榈树环绕。

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The Chazy Reef on the island contains coral, like a reef in a warm, tropical ocean.

VOA: special.2009.01.05

The boat with a crew of at least 12 was fishing for coral near Miyako island in the Okinawa chain.

BBC: Chinese boat ��illegally fishing in Japanese waters��

The 100-tonne boat with 13 crew members had been fishing for coral near Miyako island in the Okinawa chain.

BBC: Japan frees crew of 'illegal' Chinese fishing boat

Surrounded by its own coral reef, the island measures 1.5 acres and contains a Bahamian-style 4-bedroom, 3-bath home.

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