paroli - to speak, but parlamento.

regi - 'rule', but regho 'king'

okulo - 'eye', but binoklo 'binoculars'

skribi - 'to write', but manuskripto

It's not even all that well-designed and regular for a designed, regular language. In fairness, it was one of the first attempts, and before modern linguistics was even really a thing.

The modern attempt is Lojban. Based on an equal distribution of roots from the world's five major language families, with an extremely flexible grammar designed to be equally unusable by everyone. It's really quite wonderful in its precision of expression. Though one does come away thinking only a sentient artificial intelligence could use it fluently.