A crow is never the whiter for washing herself often.

乌鸦不管怎样经常洗澡，也不会变白。

Evil people are alike all over the world.

天下乌鸦一般黑。

Wherever the carcase is, there will the ravens be gathered together.

哪里有死尸，乌鸦就成群。

The crow thinks his own bird fairest.

乌鸦总以为自己的雏鸟最美。

这些谚语在英汉两种语言中都有各自的表达方式和文化内涵，希望这些信息对你有所帮助。