The answer to the first blank is: whether.
The answer to the second blank is: weather.
The first word, whether, is a conjunction that is used as a function word and it implies a kind of questioning that refers to alternatives or possibilities.
The second word, weather, is a noun and it refers to atmospheric conditions like warm, cold, wet, dry, etc.
Both words are pronounced the same but their meaning, as can be seen, is not at all the same.
