What is a sentence using the word perfidy?

A man taking a poll asked me who my favorite candidate was; what a foolish notion!Prior to the 15th century, many scientists dismissed a rotating Earth as a foolish notion.

As Tom placed the petre dish, containing the anaerobe bacteria, into the chamber and flipped the switch to suck out the atmosphere, he wondered about the kind of life that could survive in the...

Some people say it's 'their word against mine'. They wrote a 600 word essay.

Mrtin luther king jr was a baptist minister.

The sick and contaminated were put in quarantine away from the others.