Mother wanted to know how much money he(?) on cellphones是had spent 还是spent
问题描述：
Mother wanted to know how much money he(?) on cellphones是had spent 还是spent
答
had spent
分析：
wanted to know 这件事已经过去了,他花钱是在wanted to know 之前的事,是“过去的过去”.所以要用过去完成时.