I decided to buy a birthday cake ( )my mother on her birthday.括号中应填to还是for?其中有什么语法

问题描述:

I decided to buy a birthday cake ( )my mother on her birthday.括号中应填to还是for?其中有什么语法

应该填for,为
I decided to buy a birthday cake for my mother on her birthday .
buy sth for sb= buy sb sth
为某人买某物