In Portuguese, there are two verbs that mean “to know.” One is the verb saber, which is used when one is referring to knowing something such as facts or information that can be reproduced or the ability to do something. For example, if you were to tell someone, “He knows when to arrive,” you would use the verb saber (“Ele sabe quando a chegar”). Another example is “they know how to write in Chinese” (“Eles sabem como escrever em chinês”). This last example demonstrates the ability to be able to do something.
The second verb, conhecer, is used when one wants to communicate that they are familiar with a person, place, or thing. For example, if you want to say that you know someone, you would use the verb conhecer. “They know Roberta” would be said “Eles conhecem Roberta.” Same thing with a place. “Ele conhece Brazil,” or “he knows Brazil.” If you have met someone or been to a place, you can also use the verb conhecer. For example, “Eu conheci São Paulo” can mean that you both know the city of São Paulo or that you have been there. “Ela conheceu Maria” or “She met Maria” also has a similar meaning.
Here are some more examples:
Ele sabe que os Estados Unidos tem 50 estados.
He knows that the United States has 50 states.
Ele sabe como dizer tudo em inglês.
He knows how to say anything in English.
Eles sabem dirigir um carro?
Do they know how to drive a car?
Eu sei que o Carlos é português.
I know that Carlos is Portuguese.
Você conhece a música do Marcelo D2?
Do you know the song by Marcelo D2?
Ela conhece Michael.
I know Michael.
Eles conhecem a Europa.
They know Europe.
Eu conheço esse film.
I know this movie.