You cant since ferocity is a noun, it wont be able to be in a sentence
(Another word for ferocity is ferociousness, being fierce, cruel or savage.)"I decided to stay away from the jungle because of the ferocity of the cannibals who lived there." "His eyes conveyed his...
I have decided to clean out my garage next week. - as a verb we are having a clean out at home on the weekend. - as a noun
Example sentence - I heated the water in the kettle to make tea.
When I prepare to write a speech, the idea summary will be found in the topic sentence.