he did not use to give his mother many problems

问题描述:

he did not use to give his mother many problems

翻译:他过去不经常给他妈妈添麻烦.
used to表示“过去常常”,强调与现在的对比.像这个句子就暗示现在他总给他妈惹麻烦.used to的否定形式是used not to或didn't use to,该句中的用法显然是后者.
PS:这是新课标(Go for it!)初三英语书中第二单元阅读里的句子,你很认真,学英语要加油!