bottomryn.船舶抵押契约；冒险贷借bottomn.底部；底端adj.底部的v.触底；打(基础)bottom pour ladle底注式浇包,漏包bottom-dump car底卸车bottom well tools井下工具bottom door hinge底门折页bottom slot layer下层绕组bottom stow cargo打底货bottomless market行情无止境暴跌bottom allowances底裕度bottomland region滩涂区bottom dead point下止点

1. Riggers and signal persons also need standard training and testing to ensure safety under the hook.
   装配工人和发信号的人也需要标准的培训和测试，以确保安全下钩。