which,in which,on which,for which ,of which 有什么区别,在定语从句中怎么用?

选A.
which在限制性定语从句中就是指先行词,如题中的which就指先行词the day,在从句中作动词forget的宾语.
"介词+which"不能只从意思上区别,介词的选择主要有3方面
1,考虑先行词与介词的固定搭配.
This is the farm on which he is working .
on the farm 是固定搭配.
2,考虑句意的需要.
This is a factory into which he wants to go .
go into the factory .
He is one of my friends with whom i am living .
live with sb .
3, 考虑 定语从句谓语动词的固定短语所需什么介词.（这种情况尤为多些）
This is a book in which i am interested .
be interested in sth .