The capital library can come in again after going out. The Capital Library implements free borrowing, and can borrow documents with a valid reader's card with borrowing function. To apply for a reader's card, you need to bring your second-generation ID card to the self-service accreditation machine, or bring the original ID card (including ID card, household registration book, military ID card, driver's license, foreign passport, Hong Kong and Macao ID card, Taiwanese card) to the main service desk for manual processing. Unlimited time, unlimited times. This shows that the capital library can come in again after going out.