It is better to keep a wolf out of the fold than to trust drawing his teeth and talons after he shall have entered.

It is better to keep a wolf out of the fold than to trust drawing his teeth and talons after he shall have entered.

与其指望狼一进门就咬牙切齿，还不如把它赶出羊圈。

-- Thomas Jefferson 托马斯·杰斐逊