I knew from past experience that alternative therapies could help.
我知道根据以前的经验其他的治疗方法可能有效。
Your past consists of all the things that you have done or that have happened to you.
经历
It was past midnight.
过了午夜。
Most stores have remained closed for the past three days.
在刚过去的3天里大多数商店一直关着门。