Решение:
- The discovery of America was made in 1492 by Christopher Columbus.
- We'll have to stay at this hotel. There's no choice.
- He considered himself a failure. He hadn't succeeded in anything.
- The frequency of this bus service is about one every ten minutes.
- My uncle is a figure of some importance in the academic world.
Ответ: 1. discovery; 2. choice; 3. failure; 4. frequency; 5. importance.