I borrowed XXX RMB on X, X, X, with XX% interest, and promised to pay it off before X, X, X; The loan method is XXX credit card. Borrower: His signature date stipulates that credit cards cannot be lent out, so you can only prove the debt relationship between you in the form of IOUs. If he doesn't repay the bank, you can only repay it, and then ask him for debts, because the bank will pursue your responsibility.