rescue equipment consisting of a buoyant belt or jacket to keep a person from drowning
life preserver的用法和样例:
例句
A silky fiber obtained from the fruit of the silk-cotton tree and used for insulation and as padding in pillows, mattresses, and life preservers. 木棉一种绢状纤维,从木棉树的果实中提取出来,用作隔音材料,也可用作枕头,褥垫和救生用具中的垫料