他的胸部凹陷，使得他的肋骨更加明显。

He has a ___sunken chest, which makes his ribs more prominent.

我们在湖底发现了一个沉没的宝箱。

We found a ___sunken treasure chest at the bottom of the lake.

他瘦了很多，脸颊都凹陷下去了。

He lost a lot of weight, and his ___sunken cheeks were noticeable.

她因长期失眠而双眼凹陷，看起来很憔悴。

Her ___sunken eyes showed exhaustion from months of sleepless nights.