单项选择题
A.riding pawl B.devil's claw C.buckler plate D.spill pipe
A.right at the bow B.one-third the length of the vessel from the bow C.one-half the length of the vessel from the bow D.two-thirds the length of the vessel from the bow
A.force the warped，bulged，or deformed sections back into place B.support and hold the area in the damaged position C.withstand subsequent additional damage D.make a watertight seal at the damaged area