This is the 585th most frequent Romanian word.
ambele
"Ambele" means "both" in English.
The word 'ambele' is used here as a pronoun meaning 'both' to refer to the plural noun 'cărți' (books) previously established.
Ambele cărți sunt interesante.
Both books are interesting.
In this sentence, 'ambele' works as a pronoun that refers to and quantifies the noun 'profesoare' (teachers), indicating two of them.
Am vorbit cu ambele profesoare ieri.
I spoke with both teachers yesterday.
Here, 'ambele' modifies the noun 'soluții' (solutions) and specifies that all two suggested solutions were approved.