养蚕是为了得到蚕丝.Silkworm culture is practised in order to get silk.在蚕丝中, 更确切地讲,这些链是反向平行的.In silk, it would be better to describe the chains as being antiparallel.请描述蚕丝与蜘蛛丝的分子结构.Describe the molecular structures of silk and the...
戒指内侧有一层厚厚的锈斑。The tarnish lay thick on the inside of the ring.她低下头轻吻大主教的戒指。She bowed her head and kissed the Archbishop's ring.她戴了好几个钻石戒指。She wore several diamond rings....