This is the 13423rd most frequent Swedish word.
uppmärksam
Attentive.
Here, 'uppmärksam' is used to describe someone's attentiveness or ability to observe details.
Hon var alltid uppmärksam på detaljer.
She was always attentive to details.
In this sentence, 'uppmärksam' refers to the need for focus and attention to grasp a concept.
För att förstå konceptet måste du vara uppmärksam.
To understand the concept, you must be attentive.
The usage of 'uppmärksamt' in this sentence shows its adverbial form, meaning 'attentively' or displaying focused listening.