Ser, estar and ter are irregular — each form had to be learned on its own. The good news: most Portuguese verbs end in -ar, and nearly all of them follow one regular pattern.

The recipe: take the infinitive (falar), drop the -ar to get the stem (fal-), then add the ending for the person — -o, -a, -amos, -am.

Pronoun	Falar (to speak)	Morar (to live)	Andar (to walk)	Comprar (to buy)
eu	falo	moro	ando	compro
você / ele / ela	fala	mora	anda	compra
nós	falamos	moramos	andamos	compramos
vocês / eles / elas	falam	moram	andam	compram

Morar is for where you live: Eu moro em Botafogo — I live in Botafogo.