* They are distinct languages: While Portuguese and Spanish share a common ancestor (Latin) and have many similarities, they are distinct languages with their own unique grammar, vocabulary, and pronunciation.
* Language evolution: Over centuries, both languages have evolved independently, leading to significant differences.
* No objective measure: There's no scientific way to calculate the percentage of one language that is "contained" within another.
However, we can talk about similarities:
* Shared Latin roots: Portuguese and Spanish share a significant amount of vocabulary due to their common Latin origin.
* Mutual intelligibility: Speakers of both languages may understand some basic phrases or concepts, but complete fluency is not common.
It's more accurate to say that Portuguese and Spanish are closely related languages, with both similarities and differences.