理解what remained of a bottle of medicine从句

题目

理解what remained of a bottle of medicine从句
是新四里的一课：he went off immediately to visit him,carrying with him in his pocket 【what remained of a bottle of medicine】 formerly prescribed for an indisposition of Mrs.
括号中由疑问词What引导的从句和一般的“疑问词+主语+谓语动词+句子剩余部分”的从句不同.如：Carlyle was entirely ignorant of what the bottle in his pocket contained.
这种从句应该怎样分析、理解?并请给出3个例句.

答案

remain of :剩下eg：After the flood,nothing remained of the village.把这个句子改成问句,针对nothing提问的话就是：what remained of the village?再改成从句：I do not know what remainded of the village.what...