Here are the sentences changed into indirect speech:

1. Bill asked which platform the train left from.
2. Ann asked Peter if he would tell John what she had told him the night before.
3. I told my children not to watch late-night horror movies.
4. Bessie said that the bus had been there a minute ago.
5. She replied that she would come with me as soon as she was ready.
6. Mrs. Brown told us to sit down and have some tea.
7. She asked Tom what he had said.
8. Ann asked which team had won.
9. Maurice told his wife to take off her coat.
10. Tom said that he would be back in five minutes.
11. The policeman said that there had been an accident and the road was blocked.
12. The children said that they were waiting for the school bus.
13. Mary said that her father had died a year ago.
14. Mr. Brown asked if I had to go then.