?半速后退

... slow astern 慢速后退(后退一) half astern 半速后退(后退二) full astern 全速后退(后退三) ...

?半速倒车

... half ahead 半速正车 half astern 半速倒车 half a gale 半飓风 ...

?后退二

...ahead 前进三(全速)full ahead 停车stop engine(s) 微速后退dead slow astern 后退一(慢速)slow astern 后退二(半速half astern 后退三(全速)full astern 紧急进三emergency full ahead 紧急退三emergency full astern 用车完毕,完车finished with engine(s) ...