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19. I recently went back to Paris where I was born nearly 50 years ago.
20. Do you know the music which is being played on the radio?
21. You didn't tell us the reason why we have to cut down our daily expenses.
22. The day when she left was rainy.
23. I've sent him two letters, neither of which he has received.
24. That man whose name I don't remember is an artist.
25. One of the elephants which we saw at the zoo had only one tusk.
26. That car whose engine is very good belongs to Dr.Clark.
27. Thank you very much for the present which you sent me.
28. This is Mrs.Jones whose son won the championship last year.
29. Rod Lee, whose sister I know, has won an Oscar. 
30. Is this the style of hair which your wife wants to have?