Practice with past perfect – the second step back
You have to have a past time to have something that is before that past time.
Past perfect is the second step back. The first step back is simple past.
If you have several actions in correct order, you can use simple past for them all. If you say a time and then go backwards, you have to use past perfect.
present perfect is up to NOW. Past perfect is before a past time.
Reported speech takes a step back. She said/he asked…..what s/he said or asked is before that, so it’s a step back. It’s not a question, so no inverted order. WH-Subject-Verb. She asked where the dog was now (present steps back to past). He asked who your last teacher had been (past steps back to past perfect). Step-Backs Chart
Reported Yes/No questions:Using “if”/”Whether” for Yes/No questions in reported speech