The empty shell of a snail or clam may be left behind, and if it is sufficiently durable and resistant to dissolution, it may remain basically unchanged for a long period of time.

蜗牛或蛤蜊的空壳可能会被留下来，如果足够持久和抗溶解，它可能会在很长一段时间内基本保持不变。

youdao

At last, by good luck, he found a large empty snail-shell.

幸运的是，他最后找到了一个大的空蜗牛壳。

youdao

This organization is but a empty shell.

这个机构形同虚设。

《新英汉大辞典》

"One minute Bale's Patrick is a cowering corporate geek and self-described empty shell, the next an arrogant, name-dropping smoothie, the next a hysterical wimp unable to distinguish reality from fantasy, " it said.

BBC: Christian Bale in The Dark Knight

Worse, the bug disabled essential instructions that tell the PC how to start-up, effectively reducing machines to an unusable empty shell.

CNN: FROM THE WEB

Eduardo drove at the heart of the England defence and played a cute pass into the area for Olic, the Hamburg striker coolly dribbling round a shell-shocked Carson and rolling into an empty net.

BBC: England 2-3 Croatia