17,The bed on which I sleep has no mattress
18, There wasn't any directory in the telephone box from which I was phoning
19,The chair on which I was sitting suddenly collaped
20, Mr Smith whom I had come specially to see said he was too busy to speal to me
21, I saw several houses which were quite unsuitable
22, The office to which Graham took us was filled with books
 

25,That is the man who bought her car last month
26, Those are the books which he has just bought from the bookstore
27,The students who are sitting in the front now are from China
28, I like the girl whom I met ar the party last night
29, The boy which won the race yesterday is very happy
30,The teacher who wrote it last Monday liked the composition
32, the book which was written by Jane Austen is very interesting
33, The lady to whom I spoke an hour ago gave me good advice
34, Is that the computer which your father bought last month?
35, They boy which won the race yesterday is very happy