1. The course hasn't been taught by Mr. Snow since 2008.
2. Are the students divided into four groups by her? Yes, they are.
3. Where was the key put yesterday?
4. By whom are you being looked for?
5. Whose bag has been taken away?
6. When will the party be held by her?
7. Won't the truth be told to him by you? Yes, it will.

1, mr snow hasn"t taught the  course since 2008
The course hasn't been taught by Mr. Snow since 2008.

2, does she divide the students into four groups? yes, she does 
Are the students divided into four groups by her? Yes, they are.

3, where did you put the key  yesterday?
Where was the key put yesterday?

4,  who are you looking for ?
By whom are you being looked for?

5, who has taken my bag away?
Whose bag has been taken away?

7, when will she hold the party?
When will the party be held by her?