step 7-compound words

1.  There is a class and there are rooms.
2. They are class-rooms.
3. There is  a board. It is black.
4. It is a black-board.
5. You have work. This is your book.
6. This is your work-book.
7. The Sun shines brightly to-day. To-day is a holiday. It is Sunday.
8. We have a back. We have bones. We have back-bone.
9. This is the main topic. This road is straight. This is the main road.
10. I like the sea. It is blue in color. It has a shore.I like  to play in the sea-shore.