n.茧；塑料披盖；防护喷层；宅（足不出户）
动词cocoon的现在分词.
A caterpillar must pass through the cocoon stage to become a butterfly. 毛毛虫必须经过茧的阶段才能变成蝴蝶。
Silkworms make cocoons. 蚕做茧。
A cocoon is a kind of silk covering made by an insect. 蚕茧是由昆虫制造的一种由丝组成的外包层。
Silkworms spin cocoons. 蚕作茧。
