SABER X CONHECER ( To Know ) :

Verb "To Know":
Observe the following sentence:

Eu sei falar português e inglês, mas eu não sei falar espanhol.
I can ( know how to ) speak Portuguese and English, but I can't ( don't know how to ) speak Spanish.

The verb "Saber" ( to know ) is used to talk about knowledge ( of the facts, for example ) and abilities ( as in being able to speak a language). Note that the verb Saber is NOT used in the context of knowing a person or a place. In these contexts, we use the verb Conhecer (to know)

Eu conheço João . I know João; Nós conhecemos São Paulo. We have been to Sao Paulo.