1.君子之交淡如水。
A hedge between keeps friendship green.
2.少壮不努力,老大徒伤悲。
A lazy youth, a lousy age.
3.一言既出,四马难追。
A word spoken is past recalling.
4.多行不义必自弊。
Give a thief enough rope and he'll hang himself.
5.山中无老虎,猴子称大王。
In the country of the blind, the one-eyed man is king.