"This hexacopter in my hand is a camera". I'm talking about a specific hexacopter, and I'm saying it also belongs to the set "things that are cameras". So this particular one is "a camera". "The hexacopter is both camera and flying machine" is understood to mean "Everything in the set 'things that are hexacopters' is also in the set 'things that are cameras' and also in the set 'things that are flying machines'". When you talk about an entire set or species, you say "the <set/species>". When you talk about a subset of a set or species, you omit the article. In your quote, all hexacopters are being talked about (hence "the") but not all cameras and not all flying machines are being talked about, hence the omission of the article.

Hi Johnny, We can omit the article ("a" or "the") when the noun we are describing is already specific enough. Example: Italy (not The Italy) / Paul (not The Paul). Having said that, there will be exceptions (After all, English has plenty of exceptions to the rule). Example: The Carribean / The Himalayas In your sentence, we are introducing the word "hexacopter" in a general way. It does not imply that a specific helicopter or a specific camera is used. Therefore, you can write: The hexacopter is both a camera and a helicopter. Hope this helps. Cheers, Lance

Hi! I've seen both forms being used. You can use "a" if you want or you can leave it out. But personally I think if you're writing something, for example an article, it's better to drop "a" because people tend to drop a lot of articles when they write formal things.