如果能夠挖成功地道，地道裏麵沒有水，疏鬆的沙土，地道由拱形的水泥修建。那麽灌水也會馬上漏下去，除非引海水漫灌，造成沼澤。

來源: easycity 於 2023-10-21 13:13:57 [舊帖] [給我悄悄話] 本文已被閱讀：次

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