Sure! Here’s how you can complete the sentences using the words provided:

1. She was standing at the mouth of the **cave**, and heard a noise coming from inside.
2. The birds breed mainly on sea **shores** and in sea caves.
3. They enjoyed the beautiful views of snow-capped **mountains**.
4. Very little can grow in this arid **desert**.
5. We were on a ridge above a green **valley**, with the mountains beyond it.
6. She could see **waterfalls** falling down some of the mountain sides.
7. The area we passed through was once thick **forest**.
8. They can go fishing in the **lake**.
9. Wearing a pair of trainers, he walked up the steep **hill** with the energy of a young mountain climber.
10. The fish is commonly found off the **cliffs** of Australia.

Feel free to ask if you need further assistance!