Common words:
* il (he, it)
* ils (they)
* elle (she, it)
* elles (they)
* ici (here)
* il y a (there is, there are)
* impossible (impossible)
* important (important)
* intéressant (interesting)
* incroyable (incredible)
* idée (idea)
* image (image)
* immédiatement (immediately)
* individuel (individual)
* information (information)
* inutile (useless)
* impression (impression)
* inquiet (worried)
* intérieur (interior)
* interrupteur (light switch)
* inverser (to reverse)
* île (island)
* isoler (to isolate)
Less common words:
* ivre (drunk)
* ignorer (to ignore)
* illusion (illusion)
* imiter (to imitate)
* impérial (imperial)
* indiquer (to indicate)
* insérer (to insert)
* inspirer (to inspire)
* installer (to install)
* insister (to insist)
* intriguer (to intrigue)
* invalide (disabled)
* ironique (ironic)
* irriter (to irritate)
* invisible (invisible)
* inviter (to invite)
* isolé (isolated)
* itinéraire (itinerary)
This is just a small sample of French words starting with "I". There are many more, depending on your specific needs and interests!