作为一条通常规律，大部分20英尺以上的帆船使用固定龙骨。

As only a very general rule, most sailboats over 20-something feet have fixed keels.

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后来，洛维洛借钱赚钱的方法又上了一个新台阶：他组织人设计了一条船，在安装龙骨之前，他便找到一家运输公司，说服该公司预定包租这条八字还没有一撇的船。

Later on, Ludwig carried his business to a new stage of development: He got another tanker designed, Before the keel was even laid, a common carrier was persuaded to charter it after its completion.

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型保护条：采用PVC制成，紧扣在专用龙骨上以增加与天花软膜的接触面，保护并延长产品使用时间。

U type protection: made of PVC, is closely linked to the special keel to increase the contact surface with the smallpox soft film and extended product protection, the use of time.

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