活动防浪板帆船上一活动龙骨，可以绕枢轴扯起以减少船在浅水的吃水深度 A movable keel in a sailboat that can be pivoted upward to reduce the boat's draft in shallow water.
运货船一种运货的河流用船，有龙骨但无帆 A riverboat with a keel but without sails, used for carrying freight.
船桅，桅杆一条高的（有时为分段的）垂直樯，从帆船的龙骨或甲板直立起来以支持帆和操纵装置 A tall vertical spar, sometimes sectioned, that rises from the keel or deck of a sailing vessel to support the sails and running rigging.
工人正在给那艘船安龙骨。 The workers are laying a keel of the ship.