This is the 3866th most frequent Polish word.
powinna
"Powinna" means "should" or "ought to" (feminine form).
In this sentence, 'powinna' is used to express obligation or advice, suggesting that reading the book is important before the exam.
Powinna przeczytać tę książkę przed egzaminem.
She should read this book before the exam.
Here, 'powinnaś' is employed to give advice, tailored to the second person singular, indicating taking action for better outcomes.
Myślę, że powinnaś iść wcześniej spać.
I think you should go to bed earlier.
The word 'powinniśmy' in this sentence is used in the first person plural form, advocating an action as a suggestion or responsibility for a group.