“不辨是非”可以翻译为 “fail to distinguish right from wrong” 或 “be unable to tell right from wrong”。
这两个表达都准确地传达了“不辨是非”的含义，即无法区分正确与错误、对与错。例如：
He is too young to fail to distinguish right from wrong.（他年纪太小，还不辨是非。不过此处用“too...to...”结构表达更自然，即“He is too young to tell right from wrong.” ）
Some people are so easily influenced that they are unable to tell right from wrong.（有些人很容易受影响，以至于不辨是非。）