This last theory is attractive because it gives some hope of explaining the enclosed seas, such as the Sea of Japan.

最后一种理论很有吸引力，因为它给解释封闭海域（如日本海）带来了一些希望。

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Cherbourg had a splendid harbour enclosed by a long sea wall.

在瑟堡有一个由绵延海堤环绕、风景秀丽而壮观的港口。

《柯林斯英汉双解大词典》

Because it is virtually an enclosed basin, with an outlet to the sea only 55 km wide at the Strait of Hormuz, the gulf is especially vulnerable to oil spills.

由于波斯湾实际上是个封闭的盆地，只在霍尔木兹海峡有个宽仅55公里的入海口，因此遇到溢油特别容易损害。

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The partly enclosed Baltic Sea is known as one of the most polluted seas in the world.

BBC: Sweden wants explanation on Baltic nuclear 'dumping'

The sea is enclosed and a discharge of toxic waste might cause devastating harm to the wildlife.

ECONOMIST: Oil and the seals of Kazakhstan

Nan Madol comprises a set of almost 100 stone and coral fill platforms or artificial islets separated by narrow channels and enclosed by an outer sea wall.

UNESCO: OFFICE IN APIA