By nature, men are nearly alike; by practice, they get to be wide apart.
性相近，习相远。
By others' faults, wise men correct their own.
他山之石，可以攻玉。/前车之覆，后车之鉴。/前人的过失，后人的教益。
By reading we enrich the mind.
博览群书长知识。

By constant asking, you can reach China.
逢人就问路，就能到中国。/路在嘴上。