«А» doesn't have an exact equivalent in English which is why it can be translated as "but", "and", or not at all. This means we have to learn the general sense of the word instead of using the possible translations interchangeably. In this case, it would be most natural to translate the sentence as "No, Tim's an actor, not a medic."
This might be "Brain Gas", but what is the "EM" in "EM-DASH" in the Tips and Notes? I know what the dash is all about but is it actually called an "EM" dash and is this a different kind of dash than the only one on my keyboard which is "-"? Em means eat normally so is this another meaning or is it the eat dash? :)
well... First of all - it's not important, we use "-" sign in russian everywhere except for typography :)
In theory short dash '-' is called 'дефис' in russian language. It's used for splitting part of words. For example: "как-нибудь" ("somehow") or чёрно-белый (black and white). There are a lot of rules where to put that dash, don't think about them now. long dash or em-dash in their terminology (I don't know what is EM) is used for splitting parts of the sentence. I don't like the example here because I would skip long dash in that case. Let's use the other example: Земля - планета в солнечной системе. Earth is the planet in the solar system Here long dash in used 'instead of' word 'is' - это or является.
But on russian keyboard we have only short dash, so use it everywhere if you're writing.
Thanks Zhenya! Russian seems to more efficient than other languages in that they cut out many prepositions, and using the dash to cut out even more...:) In the English language, we always go way overboard in all of the prepositions that we use. It think that sentence had 6...:)
The long one "—" is called an "em-dash" and the shorter one "–" is called an "en-dash" because the letter "M" is physically wider than the letter "N". The hyphen "-" is shorter than both. Theoretically the em-dash should be as wide as the letter "m" and the en-dash as wide as the letter "n". The English names for these come from the time of printing presses.
The answer depends on what operating system and keyboard you are using. If you are using Windows with a (physical) US keyboard you can hold down the [Alt] key while typing 0151 on the numeric keypad: "—". The initial  is important, otherwise you'll get "ù" instead. If you're using Android or iOS it will depend on which (touchscreen) keyboard you have installed. It might not even be possible on your current keyboard.
You can search the internet for how to enter an em-dash on your specific hardware and operating system to find out the answer.
In English whether you use "a" or "an" depends on the first sound of the noun or noun phrase. Use "an" before vowel sounds [aeiou] and "a" before consonants (everything else).
You can usually tell by the spelling, but some words are exceptions like:
"an hour" (the "h" is silent)
"a once-in-a-lifetime opportunity" ("once" is pronounced "wunce")
"and" is called a conjuction. It joins two phrases together: "No, Tim is an actor. He is not a medic." -> "No, Tim is an actor and not a medic." ". He is" (including the full stop) is replaced by "and" because we are still talking about Tim.
Hello, it is even easier. Just go to settings, general and keyboard, and Add the russian one!! It is very cool (at least in iphone). If you are using in the computer, use this link: http://masterrussian.com/russian_keyboard.shtml -> you can type it there, and then copy it over to duolingo!!!
Correct me if I am wrong, but shouldn't the spelling be "Нет, Тим актор - а не медик" for the sake of pronunciation? I spoke some Russian prior to this course and it sounds to me like they are saying "No Tim, not an actor, a medic" rather than "No, Tim is an actor, not a medic."