had had是过去完成时态的用法。

过去完成时由“助动词 had + 过去分词”构成，其中 前一个had 通用于各种人称，后一个had是have的过去分词，表示已经吃、已经有或其它意思。

过去完成时表示在过去某一时间或动作之前已经发生或完成了的动作，即“过去的过去。

如：1.They had already had breakfast before they arrived at the hotel. 2.She had finished writing the composition by 10 ：00 this morning. 另外还有如：have sth done 请或让某人（别人）做某事 例： The king had had his tomb built before he died.希望对你有帮助 希望采纳。