Original sentence: Fennec foxes and jerboas have furry soles so their paws don’t burn on the hot sand.
Corrected (simple fix): Fennec foxes and jerboas have furry soles, so their paws don't burn on the hot sand.
Another clear version: Fennec foxes and jerboas have furry soles that protect their paws from the hot sand.
Why these are correct (easy steps):
- "Fennec foxes and jerboas" is plural, so we use have — that is correct.
- When two full ideas are joined by the word "so" (like cause and result), put a little pause (a comma) before "so": "..., so ..."
- Or you can say it another way with "that protect" to show the furry soles do the protecting.
- "Don't" is a fine contraction to use here (short for "do not").
Short tip: add the comma before "so" or use "that protect" to make the sentence clearer.