1. This is the train by which I came. => This is the train I came by.
2. Do you know the boy to whom I was talking? => Do you know the boy I was talking to?
3. The people with whom I live are very pleasant. => The people I live with are very pleasant.
4. This is the box out of which he took the money => This is the box he took the money from.
5. I don’t know the man to whom you wrote a letter. => I don’t know the man you wrote a letter to.
6. The man from whom I got the information is a lawyer. => The man I got the information from is a lawyer.