Simple Words:
* Free
* Freely
* Freedom
Words with "free" as a prefix:
* Freebie
* Freehand
* Freelance
* Freeload
* Freestyle
* Freeware
* Freewill
Words with "free" as a suffix:
* Tax-free
* Rent-free
* Duty-free
* Interest-free
* Lead-free
Other words:
* Unfree
* Freethinking
* Free-range
* Free-spirited
* Free-for-all
Phrases:
* Set free
* Free of charge
* Free to choose
* Free speech
This list isn't exhaustive, but it provides a starting point for exploring words with "free" in them.