In the contrary school, the duck is supreme. It comes nearer to the engines with which man has 'conquered' the air, as he boasts.
参考译文:与滑翔鸟相对的另一类鸟中,数野鸭本领最高。它更近乎于人类自夸的“征服”了空气的发动机。
问题:此处with是何用法?
with which man has 'conquered' the air, as he boasts 是定语从句,修饰 the engines,这里的 with which = with the engines,表示“用” the engines 作工具来'conquered' the air。