这只动物缩回到自己的壳里。

The animal retracted into its shell.

《牛津词典》

瓢虫可以将自己的头缩回到躯体中去。

A ladybug can retract its head into its body.

youdao

我缩回空着的那只手，使劲地打了那只熊五六下。

Drawing back my free hand, I struck the bear as hard as I could for five to six times.

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Hoover Shoates got his head out of the way but not his thumb.

胡福-硕茨只来得及把他的头缩回去，却没来得及把拇指抽回。

耶鲁公开课 - 1945年后的美国小说课程节选

And Meltzoff finds that babies more often than not stick their tongues out back, suggesting some sort of social connection from one person to another, and then later on babies are mimics.

迈尔左夫发现,婴儿往往会把舌头伸出来再缩回去,表明了人与人之间的某种社会联系,也说明了婴儿是模仿者

耶鲁公开课 - 心理学导论课程节选