This exercise sounds funny in Russian. "...vělíkuju žizň" means "a grand life." "We have a grand life!"
"Máme velkou žízeň" literally means "We have a big thirst", right? Is the version "Jsme velmi žízniví" (literally, "We are very thirsty") also accepted? Which one is more common?
Yes, that's the literal translation. I can't answer your first question, but I would say that "máme velkou žízeň" is almost certainly more common, since that's the only version I've seen in various sources.
I am not sure about how to pronounce that new diacritical mark on the ñ. Am I hearing it correctly as "ng"?
It is pronounced similarly to n, but the tongue position is more backwards (palatal or intermediate between palatal and alveolo-palatal), normal n has the tong on the hard palate.
From the Tips & Notes for the Hello Skill: "ň is roughly like an n followed by a consonantal y, but it is one sound rather than a combination of two."
I would add that žízen is not plural. The literal translation, which is "We have great hunger," doesn't work in English. But it does demonstrate that, although the subject and verb in the Czech sentence are plural forms, the object is not.
It is the accusative case. The verb "mít" uses objects in accusative. The nominative case would be "velkÁ žízeň".
My answer 'We have a big thirst' was marked incorrect. I understand that 'We are very thirsty is a colloquial translation, but as an Australian English speaker, I don't see my literal answer as wrong - it is actually sometimes used (e.g. in relation to beer).
It may be regionally used, but I think it would normally cause a mark as a mistake in standard English language tests (both American and British).
OK, I will have to accept that decision, and thanks for your reply. But for the sake of argument I will point out that if you replace 'big' with 'huge', it works in English. For example, it is standard English to say 'I have a huge thirst for knowledge' or even (less metaphorically), 'By the end of the day, I had developed a huge thirst for a good beer/lemonade etc'. So I think that the expression 'a huge thirst' is quite common in English, even if 'a big thirst' isn't - and after all, 'big' and 'large' are synonyms in English. A lot depends on context, and because English has so many synonyms, what sounds awkward with one word can often be common with a synonym. So I'm thinking that if someone answered 'We have a huge thirst' it ought to be acceptable, even though it seems that 'We are very thirsty.' would be the closest English equivalent to the Czech idiom.