1. The occurrence of earthquakes in that region is quite frequent.
2. The sudden occurrence of a thunderstorm caught everyone by surprise.
3. The occurrence of a rare comet passing by Earth was a sight to behold.
4. The occurrence of a global pandemic has changed life as we know it.
5. The occurrence of a power outage caused chaos in the city.
6. The occurrence of a rare bird species in our backyard was a pleasant surprise.
7. The occurrence of a shooting in the neighborhood was a cause for concern.
8. The occurrence of a solar eclipse was a once-in-a-lifetime event.
9. The occurrence of a traffic jam delayed our arrival to the party.
10. The occurrence of a full moon often affects people's behavior.