But somehow I got my days mixed up and didn't realize the mistake until now.
可是不知道怎么回事,我把日期弄错了,而且到现在才知道这个错误。
Indeed they can have a delightful surprise when they find something useful which they did not know they owned.
确实,一旦无意之中从自己的收藏品中找到某件有用的东西时,可以给人一种惊喜的感觉。