"The young men are eating an egg."
Translation:Ti mladí muži jedí vajíčko.
Bc Czech doesn't differentiate between the present progressive and the simple present like English does (they are eating vs they eat), should an adverb like teď or some other construction be used to make it clear if you mean they're eating something right this second vs if it's something they generally eat? I tried "Ti mladí muži teď jedí vajíčko" but it was marked as wrong (I realize the English sentence didn't have the word "now" but I figured it would be acceptable to include it)
Regarding translations here, as a general rule, it's a good idea (1) not to include something that isn't in the original and (2) to make sure you account for everything that is there.
Sometimes you will come across English translations seem to include "extra" words, but that's usually because the "extra" words make the Czech sentence more intelligible when translated to English. But in his exercise, for example, there is no place in the CZ-to-EN translation for "now," because the Czech original does not include it and it is not needed in English.