We know not what is good until we have lost it.
Well begun is half done.
We never know the worth of water till the well is dry.
We shall never have friends if we expect to find them without fault.
We should never remember the benefits we have offered nor forget the favor received.
Wet behind the ears.
Whatever you do, do with all your might.
What is learned in the cradle is carried to the grave.
What's done cannot be undone.
What's lost is lost.
What we do willingly is easy.