である (literary copula)

Her manners are extremely refined.

She is one of the most distinguished painters of our time.

She has an earnest, deeply serious nature.

She has a tendency to throw tantrums.

She raised her children to be honest.

She is wealthy now.

She's currently in the hospital.

She says she's happy.

It seems she was happy.

She is currently in a meeting.

She is a member of this organization.