Here are the sentences transformed into reported speech for the wh-questions:

1. "Where does your father work?" The teacher asked me where my father worked.
2. "How many people are there in your family?" She asked Lan how many people there were in her family.
3. Tam's friend asked him how long he would stay in England.
4. "How many oranges are there in the fridge?" Tam asked Lien how many oranges there were in the fridge.
5. The teacher said to Lien what his hobby was.
6. "How do you go to the airport?" His friend asked him how he went to the airport.
7. "How much does this dress cost?" Lan asked Mai how much that dress cost.
8. Ba asked Tam how often she washed her clothes.
9. "When will your father leave Vietnam for the USA?" Phong asked Thu when her father would leave Vietnam for the USA.

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