We are often told not to regret past events, that there's nothing we can do now, considering what's already been done. However, we are also told that we can learn from the past and become better people. By reflecting on our wrongdoings and improving on them, we can do better in the future. So what should we do? First of all, it is good for the mind not to think any more if we suffer from the mistakes or unavoidable circumstances of the past, or if we scold ourselves too much. If you're struggling with what's already done and can't concentrate on your work, it's better to send the past neatly...