acknowledgingсуществительное Used as a gerund meaning 'the act of acknowledging'; functions as an abstract noun.
His acknowledging of their contribution was appreciated.
Его признание их вклада было высоко оценено.
acknowledgingгерундий или причастие настоящего времени Used attributively or predicatively to describe someone or something that acknowledges.
The acknowledging manager apologized for the mistake.
Признающий ошибку менеджер извинился.