Conversation questions often ask why a speaker came, called or mentioned something. Purposes hide in the first exchange: 'Hi, I was wondering if…', 'The reason I'm here is…'. In lectures, purpose questions ask why the professor mentions an example: to illustrate, to contrast, to correct a common belief — almost never 'to entertain'.
Attitude is carried by word choice and tone more than by statements: 'unfortunately', 'surprisingly', 'I have to admit', a sigh inside the sentence. Answers use attitude words (concerned, enthusiastic, skeptical, apologetic). Trap: an attitude the speaker REPORTS ('some people think it's a waste') is not the speaker's own.
Function questions replay a line and ask why the speaker said it: to apologize, to suggest, to clarify, to express doubt, to change the topic. The same words do different jobs in different contexts — 'That's interesting' can be genuine or politely doubtful. Always answer from the situation, not the dictionary.