The questions you ask must be on the topic so that everyone can help you. Who has a pile of reference books with him for future reference? Know what regional exam questions, how many pages are there in the book, how many pages are there in the so-and-so Olympic math question, and what regional prestigious school project software, etc. Think about how others can help you before giving the question. Besides helping you think, do you have to spend money on books to help you answer questions? The last photo or picture won't? Or the problem can't be clarified?