Woman speaks too quickly and sometimes I don't understand what she says. I'm from Poland.
Also doesn't put the accents right and sometimes loses "y" when it's the last letter of a word. :D
Decade is used usually as "10 years", so it definitely isn't a second. The sentence "Dekada nie jest sekundą" means the same.
Or "10 days", depending on a weather at Mars. That's why I hate this word and newer used it in my entire life.
Well, 'sekundy' is indeed the Genitive (dopełniacz) form, but your sentence doesn't make grammatical sense...
no it is one of those "special" sentences created to use the most new words like "January is a month of winter",
The problem of many learners is that they take the rule about negation causing Genitive too far. It is not "Negation = Genitive". It's "Negated Accusative = Genitive". And because Accusative is so commonly used, people spread this too far. But actually any other case just stays the same when negated.