The castle was built on top of a natural grassy mound.

这座城堡建在一个天然的绿草如茵的小丘上。

《牛津词典》

They built a moat to encompass the castle.

他们在城堡周围修了一条护城河。

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Now, according to legend, Slytherin had built a hidden chamber in this castle known as the chamber of secrets.

根据传闻，斯莱特林在城堡里修了一所暗室，也就是大家听说的密室。

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I was like, "it's a castle from 1400." I was like, "America wasn't even built by 1400."

我想说“建于1400年的城堡。那时都还没有美国呢。”

英国与美国的差异 - SpeakingMax英语口语达人

But he lives like a king in his 9, 000-square-foot keep on the edge of the Rocky Mountains--one of hundreds of Americans who have bought or built a castle.

FORBES: Castle 4 Sale

The children built a castle, of course, but castle-building is rather poor fun when you have no hope of the swishing tide ever coming in to fill up the moat and wash away the drawbridge, and, at the happy last, to wet everybody up to the waist at least.

NPR: Excerpt: 'Five Children and It'

King John built Odiham Castle as a stopping place where he could pursue his passion for hunting in its Royal Deer Park.

BBC: Part of the Odiham embroidery design