know yourself and know your enemy
知己知彼，百战不殆。
If you know your enemies and know yourself, you can win a hundred battles without a single loss.
汉译英翻译词典收录86165条汉英翻译词条，基本涵盖了全部常用中文字词的英语拼写、翻译、音标、读音、用法、例句等，是英语学习的有利工具。