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

答案是for。
I decided to buy a birthday cake for my mother on her birthday 。
to是至 for是为XX做某些事情

for
buy sth for sb 为某人买某物

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

应该填 :for
buy sth for sb = buy sb sth 为某人买某物