This is the 3517th most frequent Swedish word.
duktiga
"Skilled" or "capable."
Here, 'duktiga' is used to describe proficiency or skill in an activity, specifically playing the piano.
De är mycket duktiga på att spela piano.
They are very skilled at playing the piano.
This sentence uses 'duktig' to compliment someone's skill in cooking or culinary expertise.
Han är duktig på att laga utsökta middagar.
He is skilled at preparing exquisite dinners.
In this case, 'duktiga' is used to describe good behavior, effort, or diligence in a context, specifically school.