ter certeza

You will use the verb ter followed by certeza. If you want to say what you are sure about, add de. For example: Tenho certeza de que... (I am sure that...). In casual speech, people often drop the de. You can also add absoluta to the end. Tenho certeza absoluta is the ultimate 'no-doubt' card. Use it when you are ready to bet your lunch on it.

Use it when confirming plans with friends. Use it in a meeting to show you know your facts. It is perfect for answering questions like 'Are you sure we are going the right way?' Just say Tenho! or Tenho certeza. It works at the doctor's office or the grocery store. It is a very versatile, everyday phrase.

Do not use it if you are only 'pretty sure'. If there is a 1% doubt, use acho que (I think that). Brazilians and Portuguese people value the distinction. Using ter certeza and being wrong can be a bit embarrassing. Also, avoid using it to sound arrogant in a heated argument. It can come off as stubborn if overused.

Portuguese speakers can be very expressive. When they say tenho certeza, they often accompany it with a firm nod. There is a cultural value in being 'seguro' (secure/sure). In Brazil, you might hear certeza! shouted as a standalone agreement. It is a way of saying 'Absolutely!' or 'You bet!'. It builds trust in a conversation.

You will hear certeza? as a question to double-check someone. Com certeza is another huge one. It means 'Of course' or 'Definitely'. While ter certeza describes your state of mind, com certeza is a reaction. If someone asks if you want brigadeiro, com certeza is the only correct answer. It is the verbal equivalent of a thumbs-up.