Hello, I would love to answer your question as soon as possible, But I do not know fully what you are asking, can you be more specific?
Answer:
Canada is what is known as a low context communication culture. People focus on words and what is said when communicating. Canadians therefore tend to be quite direct; they tend to say what they think and think what they say. They don't rely very much on non-verbal cues.
Are you trying to learn English? because the word function doesn't fit "On the function of the textbook in the classroom is right to say that'