Get Fortified Fleet upgrade. It gives your Subs a lot more health.

举行深化舰队升级。它将会给你的潜艇更多的血量。

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Here, hidden behind fortified walls, the republic built and maintained its 9 galleons, the ships that made up its navy and much of its commercial fleet.

在这高墙壁垒之内，威尼斯共和国在这里建造并维修自己的大型帆船，这些船供威尼斯海军和大部分商队使用。

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