Помогите сделать домашнее задание пожалуйста. 1) I think diet is important

Помогите сделать домашнее задание пожалуйста.
1) I think diet is important for the/a/ sports stars.
2)I've got the/an/ exam tomorrow. It's in the/a/ afternoon.
3)Our science teacher says the/a/ cereals give you the/a/ energy.
4)This magazine article says that the/a/ olive oil is good for your skin.
5)We have the/a/ breakfast at 7 a.m. I have the/a/ piece of toast and the/a/ cup of tea.
6)I've got the/a/ football match after school. The/A/ match starts at 4.30 p.m.