I want to buy something for my family.改成一般疑问句,something变成anything吗?为什么?

something是用于肯定句中的,当用于疑问句或者否定句时一般都要改为anything.

Do you want to buy anything for your family.

Do you want to buy anything for your family
一般疑问句中SOME都要该成ANY.除非是希望得到肯定回答或发出邀请的句子
例如：
Do you want some drinks?

是的，some一般用于肯定句，any一般用于疑问句和否定句。