英语语法分析

While two of these ships sank, they were all designed with double hulls believed to make them "unsinkable", perhaps a mistaken idea that led to the Titanic's and the Britannic's tragic end.

虽然其中两艘沉船沉没了，但它们都是双层船体设计，这种双层船体被认为是“永不沉没的”，也许正是这个错误的想法导致了泰坦尼克号和不列颠号的悲剧结局。

It was billed as an unsinkable ship due to its construction.

通过它的建造方法来看，它被造得像永不沉没的轮船。

Which great ship, said to be unsinkable, sank on its maiden voyage?

什么船人称“不落之船”，却在其首航时沉没？