IPA: /ˈfɜː.vənt.li/
KK: /ˈfɜrvəntli/
In a way that shows intense and passionate feelings.
She fervently believes in the importance of education for all children.
Fervently → It is formed from "fervent" (from Latin "fervens", meaning boiling or glowing) and the suffix "-ly" (meaning in a manner of). The word "fervently" means in a manner that is passionate or intensely enthusiastic, akin to the heat of boiling.
Think of something that is 'boiling' ('fervens') with passion or intensity — that's why fervently means to do something with great enthusiasm.