Formal:
* The landscape was characterized by sharp declivities that made travel treacherous.
* The explorer's map showed a series of declivities and elevations leading to the hidden valley.
* The ancient city was built on a series of declivities, with temples and palaces perched on the highest points.
Figurative:
* The politician's speech was full of empty promises, leading the audience down declivities of disillusionment.
* The author's descriptions of the characters' emotional journeys were so vivid, it was as if we were navigating the declivities of their hearts.
* The stock market experienced a sudden drop, sending investors down the declivities of despair.
Descriptive:
* The steep declivities of the canyon walls made it difficult to reach the river below.
* The hikers carefully traversed the declivities of the mountain trail, taking in the breathtaking views.
* The park was filled with rolling hills and declivities, creating a picturesque landscape.
Note: "Declivity" is a formal word that is not used very often in everyday conversation. It's more common in technical writing or when describing geographical features.