Simple rephrases:
- The fossa climbs and runs so well that it is a very good hunter.
- Because it can climb and run fast, the fossa can catch other animals to eat.
- The fossa is a great climber and runner, so it can catch its food easily.
What 'hunter' means: A hunter is an animal that finds and catches other animals to eat.
How I changed the sentence (easy steps):
- Find the main idea: the fossa is good at climbing and running and that helps it hunt.
- Use simple words a 6-year-old knows (climb, run, catch, food).
- Make a short sentence and show the cause with 'so' or 'because'.
If you want, I can make the sentence even shorter or turn it into a sentence for a picture book.