People used to say in olden days that no boat returns after having once entered the 'black waters' of the ocean.

人们过去习惯说一旦进入大海的‘黑水’，没有船能够回来。

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Tsarnaev, who had appeared in surveillance photos wearing a black cap and was identified as Suspect No. 1, died days after the April 15 bombing, which killed three people and injured more than 260 others.

NPR: Uncle Arranging Boston Bomb Suspect's Burial Rites