蚕宝宝吐丝把自己包裹在茧里，准备变成蛾。

The silkworm spins a ___cocoon around itself to prepare for becoming a moth.

她坐在柔软的沙发里，被毛毯和枕头形成的温暖保护层包围着。

She sat on the soft sofa, surrounded by a warm ___cocoon of blankets and pillows.

她喜欢用毯子把自己裹起来，隔绝外界的寒冷。

She likes to ___cocoon herself in blankets to keep out the cold.