1- она могла хорошо петь когда ей было 10 лет 2- когда вы смодиие написать письмо ? 3- нина возможно знает его адрес пепевод ! на язык

1. She could sing very well when she was ten 
2. When you can write a letter?
3. Nina may be know his address

She could sing very well when she was 10 years old

When you are able to write a letter?
Nina may know his address