17. I recently went back to Paris. I was born in Paris nearly 50 years ago.
-> I recently went back to Paris, in which I was born nearly 50 years ago.
18. Do you know the music? It is being played on the radio.
-> Do you know the music which is being played on the radio?
19. You didn’t tell us the reason. We have to cut down our daily expenses for that reason.
-> You didn’t tell us the reason for which we have to cut down our daily expenses.
20. The day was rainy. She left on that day.
-> The day on which she left was rainy.
21. I’ve sent him two letters. He has received neither of them.
-> I’ve sent him two letters, neither of which he has received.
22. That man is an artist. I don’t remember the man’s name.
-> That man, whose name I don’t remember, is an artist.