give a dog a bad name and hang him这句话的字面意思给一条一个坏的名字（罪名），并且吊死它。实际意思是：给别人强加恶名来毁掉他，可翻译为人言可畏。

【例句】
Give a dog a bad name and hang him is true in george's case, for no in ever has a good word to say for him now.
人言可畏，乔治的情况便是如此，现在没人替他说一句好话了。

Give a dog a bad name and hang him is true in today’s case. For no one ever has a good word to say for the young lady.
一旦给别人加个坏名声，他就永远洗不掉了。今天的案例就是如此。现在谁也不替这位年轻的女士说句好话了。