With: "Both rivers, the Amazon and the Orinoco, and their respective basins", why does Amazon get pluralized to "Amazonas"? I've seen that the masculine is "el Amazonas" and the feminine is "la Amazona". Why is that, please? I'm wondering about the use of "el río Amazonas" versus "la selva Amazona" and "la selva Amazonica".
How does "se nos" change the meaning of "Uno de esos ríos que enseguida viene a la mente" -v- "Uno de esos ríos que enseguida se nos viene a la mente".
And the use of "ello" . . . does "ello" not mean "it" or "that"? Is the use of "ello" as "this" merely the uneducated English useage where "this" and "that" and their appropriate relationships to time and place become misused? : "An example of that is Caño Cristales, a natural sanctuary."
And why the use of the future tense "existirán en otros lugares del mundo"?