The channel in the Black Sea, although much smaller, is the only one to be found still flowing and proves that these mysterious channels are formed by underwater rivers.

在黑海中的这条通道，虽然很小，但却是唯一一条已被发现仍然流动的通道；它也同时证明，这些神秘的通道是由水下河流所形成的。

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The channel in the Black Sea, although much smaller, is the only one to be found still flowing and proves that these mysterious channels are formed by underwater rivers.

在黑海中的这条通道，虽然很小，但却是唯一一条已被发现仍然流动的通道；它也同时证明，这些神秘的通道是由水下河流所形成的。

youdao