I had a nagging feeling that I had forgotten something.

有某种不安的，好像忘了什么东西似的。

I had a queer sensation as if a worm was creeping down my spine.

有种可疑的, 好象有个虫子在顺着的脊梁往下爬似的。

He felt a species of uneasiness.

他有种不安的。