Questions & Answers about Jak długo trwa ta epoka?
Why is ta epoka in the Nominative case if this lesson is about the Genitive?
Ta epoka is the subject of the sentence—it is the thing that is 'lasting.' The Nominative is the basic form used for subjects. The Genitive case taught in this lesson will only appear in the answer to this question, triggered by the prepositions od (from) and do (to).
How would I answer this using the od ... do ... (from ... to ...) structure?
You would start with (Ta epoka) trwa... and then add your time boundaries in the Genitive case. For example: trwa od maja do sierpnia (it lasts from May to August).
I often confuse trwać with zajmować. When do I use which?
Use trwać for things that 'last' or have a duration on their own, like an era, a movie, or a meeting. Use zajmować (to occupy/take) when an activity takes up someone's personal time to complete, like To zajmuje mi godzinę (It takes me an hour).
Could I ask Jak dużo czasu instead of Jak długo?
Yes, but Jak długo (literally 'How long') is the most natural and common way to ask about the duration of an event or period. Jak dużo czasu (How much time) is better when asking about a quantity of time someone has available, like asking 'How much time do we have left?'