Here is a clearer way to write your sentence:
Corrected: Mountain plants grow in bunches. This helps them hold onto the slope and not dry out.
Why this is better (simple steps):
- Use "This" to point back to the idea in the first sentence. It makes the meaning clearer than just "It."
- Say "not dry out" instead of "not get dry." "Dry out" is a natural way to say something loses its water.
Another easy version: Mountain plants grow in bunches. This helps them stay on the slope and keep from drying out.
Nice work! You're making good sentences — keep practicing short, clear ideas like this.