Each of the TV programmes below is a spin off from another, earlier programme. Name the original.
1. The Green Green Grass
 Only Fools & Horses
2. Tabitha
3. Frasier
4. Jason King
 Department S
5. Ashes to Ashes
 Life on Mars
6. Going Straight
 Porridge (which in turn was from "Seven of One")
7. Lewis
 Inspector Morse
8. Take Hart
 Vision On
9. OTT
10. Benson