adj.下沉的
n.下沉；凹陷；虚脱感
动词sink的现在分词形式.
When they didn't get back by midnight, I got that sinking feeling. 他们到半夜时还没回来，我感到心神不定。
He could not control the sinking of his legs. 他无法控制他的腿的下沉。
