改成过去完成时his parents gave Tom a pen.

问题描述:

改成过去完成时his parents gave Tom a pen.

his parents had given Tom a pen

His parents had given Tom a pen.
过去完成时结构: had + 过去分词

his parents had given Tom a pen .
过去完成时(past perfect)表示在发生在过去的两个动作在前的那一个,它表示句子中描述的动作发生在“过去的过去”.
基本结构 主语+had+过去分词vpp.(done)