Learn Portuguese (Portugal): Aquele esqueleto não pertence a um réptil, mas sim a uma ave. - That skeleton doesn't belong to a reptile, but rather to a bird.

Aquele esqueleto não pertence a um réptil, mas sim a uma ave.

That skeleton doesn't belong to a reptile, but rather to a bird.

Breakdown of Aquele esqueleto não pertence a um réptil, mas sim a uma ave.

a / an / some (all forms)

Questions & Answers about Aquele esqueleto não pertence a um réptil, mas sim a uma ave.

What is the exact difference between using just mas and using mas sim in this sentence?

While mas simply means 'but' and introduces a contrast, adding sim creates a strong corrective opposition meaning 'but rather' or 'but instead'. You use não... mas sim when you want to completely reject the first statement and replace it with the second one.

Why do we need the preposition a again before uma ave?

The verb pertencer (to belong) requires the preposition a. When using a corrective structure like não... mas sim, the two opposing parts must be grammatically balanced. Because we said a um réptil in the first half, we have to repeat the preposition for a uma ave in the second half.

Could I use the word pássaro instead of ave here?

You could, but ave is much more natural in this context. Pássaro usually refers specifically to small perching birds or songbirds. Ave is the broader, more scientific term for any bird, which perfectly fits a conversation comparing skeletons and animal classes.

Why use Aquele instead of Esse for 'That'?