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1. The boy with whom Peter shared a flat was a philosophy student and wanted to sit up half the night discussing philosophy./ The boy whom Peter shared a flat with was a philosophy student and wanted to sit up half the night discussing philosophy.
2. They gave me four very bad tyres, one of which burst before I had driven four miles.
3. She climbed to the top of the monument to see the wonderful view about which she had been told. / She climbed to the top of the monument to see the wonderful view which she had been told about.
4. I was given this address by a man whom I met on a train.
5. The bar from which I was telephoning was so noisy that I couldn't hear the person at the end of the line. / The bar which I was telephoning from was so noisy that I couldn't hear the person at the end of the line.
6. The man who answered the phone said Tom was out.
7. The horse which I was on kept stopping to eat grass.