1. i have sent him who has received neither of them, two letters.

2.that man whose name i don't remember, is an artits.

3.you sent me a present ,which thank you very much for.

4.this is mrs.jones ,whose son won championship last year

5. the book in which we can look up telephone numbers, is a telephone directory.

6.the airport where we are going to arrive, is the most mordern one .