(a)"No wonder it looked familiar. This order number has been used before."(b) No wonder it seemed familiar.This order number had been used before."这是你的意思么? ="难怪它很看来熟悉, 原来这个订单号以前使用过."注: 难怪=no wonder; small wonder; not surprised at all.1. No wonder he couldn't come.2. Small wonder he couldn't make it tonight.3. I am not surprised at all that he couldn't come.