三道英语单选题 说明原因!

题目

三道英语单选题 说明原因!
1.I shall never forget the days —— we stayed together on the farm.
A that B which C when D why
2.Mother has bought all —— is necessary for New Year‘s Day.
A what B which C that D because
3.My hometown isn’t —— it used to be ten years ago.
A what B who C where D which

答案

c the days 在从句中做时间状语
c 先行词是不定代词 只能用that
表语从句,.的样子,选a