Помогите пожалуйста а то завтра убьют)

Paraphrase  the sentences using past perfect.

Example:    I went to see Boris, but he wasn't in ( to go out)     

                          I went to see Boris, but he had gone out.

1) I saw Helen yesterday, she was the same as before ( not to change a bit).

2) Mum gave me a sandwich to eat but I wasn't hungry ( to have breakfast).

3) We wanted to go to country  by car but we couldn`t ( to break down).

4) I was going to do the flat but it was clean thanks to my sister ( to clean the flat).

5) When I came home and wanted to help my mum, the dinner was on the table ( to cook dinner).

I saw Helen, she hadn't changed a bit.Mum gave me a sandwich but I wasn't hungry, as I had already had breakfast.We wanted to go to the country, but the car had broken down.I was going to do the flat, but my sister had already cleaned it.When I came home and wanted to help my mum, she had already cooked dinner.