This is the 10422nd most frequent Portuguese word.
extenso
"Extenso" means "extended" or "in full."
In this context, 'extensa' is used to describe the physical length or size of the avenue, emphasizing its considerable range.
A avenida principal da cidade é realmente extensa.
The main avenue of the city is really extensive.
In this sentence, 'extenso' is used as an adjective describing the document as being lengthy or containing many pages.
O documento estava muito extenso, com mais de cem páginas.
The document was very extensive, with over a hundred pages.
Here, 'extensa' is used as an adverb modifying the verb 'respondeu', indicating that the answer was detailed or elaborated upon thoroughly.