[عاطف القاضى]

I think the following sentences are both correct:
"1970 was the year when my mother was born
"1970 was the year that my mother was born in
When we use relative pronouns, we can use "where" as well as "which in or in which" with places whereas we can use "when"as well as " which on/in", "on/in which','that in/on "with adverb of time
EX-1- Alexandria is the place where I was born
2- Alexandria is the place which I was born in
3- Alexandria is the place in which I was born
4- January is the month when I was born
5- January is the month that I was born in
6-Monday is the day when my wife goes shopping
7- Monday is the day which my wife goes shopping on
8- Monday is the day that my wife goes shopping on