The Monkey King didn't know that "Pi Ma Wen" was a lowly position.He was pleased to have gotten the post.He kept himself busy grooming the heavenly horses day and night.He labored in this way for half a month.One day,all of the grooms were sitting together drinking wine.The Monkey King abruptly asked,"What kind of post is 'Pi Ma Wen'?"One of the grooms answered,"It's a most unimportant post,quite like head groom."