The books mentioned in the text are mainly about ______.

(单选题)What does the expression “money with no strings attached” in (单选题)Why does the author like doing volunteer work? (单选题)What can we learn about the parent from paragraph 3? (单选题)What does the underlined phrase “tug at the heartstrings” in (单选题)What can we infer about the parent from her reply in paragra (单选题)The shared goal of GDA’s projects to ______. (单选题)The program beginning in August will operate in ______. (单选题)What is the main responsibility of volunteer managers? (单选题)25.（ ） (单选题)24.（ ）