Can you please check these sentences for me? Thank you very much. It is really urgent!

1) She was looking at the people sitting at the cafè while she was driving.
2) She was listening to music on her earphones while she was running in the park.
3) She was looking at a mobile phone shop window while the police arrested her.
4) The children were riding their bikes in the park while the telephone rang.
I would go on holiday to (or at?) a seaside resort, if I had the money.
5) I would give part of the money to charity (or to a charity), if I won the lottery.
6) I doubt if I'll win the race.
I doubted if I would win the race.
They say he is going to win the race.
He is said to be winning the race.
They say he has won the race.
7) He is said to have won the race.
They say he has been teaching English.
He is said to have been teaching English.
8) At school I mustn't play truant, prompt a classmate or forge my parents' signature.
I have to (or must?) listen carefully to the teachers' explanations, take notes and do my homework regularly.

1 and 2 are OK.

3) She was looking in a mobile phone shop window when the police arrested her.

4) The children were riding their bikes in the park when the telephone rang.
I would go on holiday to a seaside resort, if I had the money.

5) I would give part of the money to charity, if I won the lottery.

6) OK

7) OK

8) I mustn't be truant from school, prompt a classmate, or forge my parents' signature. I don't know what "prompt" means in that sentence. ??

I must listen carefully to the teachers' explanations, take notes, and do my homework regularly.