He has an 'impressive' vocabulary for a 10-year-old.
a large and 'impressive' [='imposing'] building
Her first performance was very 'impressive'.
(..) - You have your-- - My mother's eyes, yeah. Lily, lovely Lily. She's exceedingly bright, your mother. Even more impressive even though I could say that she was Muggle-born. One of my best friends is Muggle-born. - She's the best in our year. (..)2009 Harry Potter and the Half-Blood Prince