社會不知道怎樣處置慣犯。

　　Society does not know how to deal with hardened criminals.

　　他知不知道有什么關系嗎？

　　What difference will it make if he knows or not?

　　她不知道自己如何弄得如此狼狽不堪。

　　She wondered how she had got into this unholy mess.

　　我不知道該不該穿外套。

　　I wonder if I should wear a coat or not.

　　我們不知道他是死是活。

　　We don't know whether he's alive or dead.