Ver vs. olhar
While both ver and olhar relate to the sense of sight in Portuguese, they are not interchangeable. The core difference lies in intention: ver is the passive ability or result of seeing, whereas olhar is the active and deliberate action of looking.
Ver
A1The verb ver translates to to see. It describes the passive sense of sight, the ability to perceive with your eyes, or the result of that perception. It is often unintentional. It can also mean to watch (like a film or TV show), to understand, or to visit someone.
Eu abri a janela e vi um pássaro.
(I opened the window and I saw a bird.)
Ele precisa de óculos para ver melhor de longe.
(He needs glasses to see better from afar.)
Nós vamos ver o novo filme no cinema.
(We are going to watch the new movie at the cinema.)
Depois da explicação dele, eu finalmente vi o meu erro.
(After his explanation, I finally saw my mistake.)
Vou ver os meus avós no próximo fim de semana.
(I'm going to see/visit my grandparents next weekend.)
Pode ver se o correio já chegou, por favor?
(Can you see if the mail has arrived yet, please?)
Olhar
A1The verb olhar translates to to look. It describes the active, intentional action of directing one's eyes towards something or someone. It implies focus and purpose, and is often followed by the preposition para (at/to).
Olhe para mim quando eu falo com você.
(Look at me when I'm talking to you.)
Ele olhou pela janela para ver se estava a chover.
(He looked out the window to see if it was raining.)
Ela passou a tarde a olhar para o mar.
(She spent the afternoon looking at the sea.)
Não olhes para o sol diretamente, faz mal aos olhos.
(Don't look directly at the sun, it's bad for your eyes.)
O detetive olhou cuidadosamente para todas as pistas.
(The detective looked carefully at all the clues.)
Você pode olhar as minhas malas por um instante?
(Can you look after my bags for a moment?)
Summary
In essence, ver (to see) is often the consequence, while olhar (to look) is the action. You must first olhar para (look at) the sky in order to ver (see) the stars. Think of ver as what happens passively when your eyes are open and functioning, while olhar is what you do intentionally with your eyes.