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2.A man who answered the phone told me you were away
3A waiteress who served us was very impolite and impatient
4 A building which has been rebuilt was destroyed in the fire
5 A bus which runs every half hour goes to the airport
6 I saw the man who closed the door
7 The girl who won the race is happy
8The student who sits next to me is from China
9 The taxi driver who took me to the airport is friendly
10 The woman who answered the phone was polite
11 The man who sang at the concert has a good voice
12 We enjoyed the actors who played The leading roles