你的两句改写都是错的。

正：It has become necessary to punish the offenders.

误：It has become necessary the punishment of the offenders.

误：It has become necessary the offenders's punishment.

后面两个句子出错的主要原因是名词短语通常不外置（至于其他的小错还不是重点,如你的第三句所有格多了一个s）。