All 3 Uses

acknowledge
in
Touching Spirit Bear
(Edited)

His parents hadn't even acknowledged each other.
Chpt 4

acknowledged = recognized
As the Circle sat down, the Keeper drew in a deep slow breath, looking around to acknowledge each person.
Chpt 4 *

acknowledge = express recognition of
Cole acknowledged Edwin's words with a weary grunt and struggled on without complaining.
Chpt 18

acknowledged = recognized

Definitions:

(1) (acknowledge as in: acknowledge her or the truth)
express recognition or appreciation of someone or something; or to admit or express something
(2) (meaning too rare to warrant focus)
Specialized senses include sending an "acknowledgement" (letter or other message) to indicate that something was received and the "acknowledgements" section at the beginning of a book where an author recognizes and thanks other people who helped in creating the book or ideas contained in it.