Write the next sentence in the following story.

How to add nitrogen to compost
Add fresh grass clippings to the compost.
Collect the grass clippings left after you mow your lawn. Add the clippings in thin layers to the compost so that it doesn't clump up into big chunks.
Make sure that your grass clippings are fresh because dried grass clippings will add carbon to the compost. Add leafy plant clippings to the compost.