wheels withinwheel: n. 1.轮,车轮;轮状物。 2.〔口语〕脚踏车;【造船 ...复杂: complex; complicated的: 4次方是 The fourth power of 2 i ...结构: structure; composition; cons ...复杂的结构: complex structures下载手机词典可随时随地查词查翻译