Definition
To be helpful or useful to someone; to provide assistance or service to someone.
為（某人）效勞；對（某人）有幫助
I am happy to be of service to you, please let me know what you need at any time.
我很樂意為您效勞，請隨時告訴我您需要什麼。
The staff at this hotel are always ready to be of service to their guests.
這家酒店的工作人員隨時準備為客人服務。
As a part of the team, I'm always ready to be of service to the group.
作為團隊的一員，我隨時準備為團隊效勞。