tolong dibantu dong pliss bahasa inggris write these active voices into passive voices

1.A letter written by me every week 2.The bus waited by John now 9.The cake has cooked by my mother for 2 hours

1. A letter is written by me every week
2. The bus is being waited by john now
3. English has been studied by them for 3 hours
4.  I was called by my uncle yesterday
5. Lunch was being had by the teachers
6. They had been invited by us for the party
7. The picture will be painted night
8. The piano can be played by cathy well
9. The cake has been cooked by my mother for 2 hours
10. The tree was cut buy the students yesterday