Eu quero comprar uma chave nova.

I want to buy a new key.

Breakdown of Eu quero comprar uma chave nova.

• eu: I
• querer: to want
• comprar: to buy
• uma: a

Questions & Answers about Eu quero comprar uma chave nova.

Why is uma used instead of um?

Because chave is a feminine noun in Portuguese. Feminine nouns take the indefinite article uma, while masculine ones take um.

Why is nova used instead of novo?

Since chave is feminine, the adjective following it also needs to agree in gender. That’s why nova is used (feminine form), rather than novo (masculine form).

Do I need to use Eu at the beginning, or can I just say Quero comprar uma chave nova?

You can omit Eu because in Portuguese the subject is often understood from the verb’s ending. However, saying Eu quero comprar... is perfectly fine and sometimes adds emphasis.

Why do we say quero comprar instead of just quero?

Quero alone only means "I want". Including comprar (to buy) clarifies exactly what you want to do, forming the full expression "I want to buy".

Why isn’t it uma nova chave instead of uma chave nova?