retracts的例句（retracts在句子中的用法）

• The nose unit is twin - wheeled and retracts rearward. 前鼻单元是双轮并向后收起.
• A cat retracts its claws. 猫缩进它的爪子.
• A totally hypothetical high - speed , Metalclad carrier . The control car retracts into hull to lower wind resistance. 一架设想中的 高速 全金属硬式飞艇,为了降低阻力,控制仓能够缩进蒙皮中.
• The split graph is given endomorphism images are retracts. 给出了任意自同态像图都是收缩核的分裂图的结构.