單詞devil的首字母d需要大寫嗎

不需要大寫。

He was a miserable old devil.

他真是個令人厭煩的老傢伙。

He's a crafty old devil.

他是個奸詐狡猾的傢伙。

The leader seemed the devil incarnate.

那個首領好像是魔鬼的化身。

I miss the old devil， now that he's gone.

老傢伙這一走，我還真想他。

She has convinced herself that she is possessed by the devil.

她確信自己被魔鬼附了身。