Sometimes when you are reading or listening, a part does not make sense. That mixed-up feeling has a name: not understanding. Good learners notice this feeling right away, instead of reading or listening past it.
Zara is listening to directions for a game. Halfway through, she thinks, 'Wait, I don't get how the second part works.' She notices the confused feeling and stops to think about it, instead of just nodding along.
One clue that you don't understand: you cannot say the idea back in your own words. If you cannot picture it or explain it simply, that is your signal to pay closer attention.
Theo is reading a story. One sentence feels like a jumble of words. Instead of skipping past it and hoping it will make sense later, he notices, 'That sentence confused me,' and rereads it.
The confused feeling is not bad, it is useful. Noticing it is the first step to understanding.
You are listening to a story and one part doesn't make sense. What should you notice?