Legal analysis: 1, it is also possible to write IOUs between husband and wife. At this point, the writing of IOUs is generally the same as that of ordinary IOUs. 2. In order to make the IOUs valid, we need to pay attention to the following matters: (1) IOUs should be written by borrowers, but we should pay attention to the writing standards. Printed IOUs have the same legal effect, but they are easy to forge. The borrower's signature should also be thumbprinted. The borrower's information must be clearly written with the ID number, and the borrower should be required to provide the original for verification when writing the loan. (2) the date of borrowing-be sure to write clearly, and it is best to be accurate to the day. The repayment date can be agreed on the loan slip. If there is no agreed repayment date, the borrower can claim repayment at any time. If the repayment date is agreed, the request can only be made when the repayment date expires. If the repayment date is not returned, the lender shall file a lawsuit within three years, and may lose the right to win the case after the deadline. (3) The loan amount should be capitalized in Arabic numerals and Chinese at the same time, and the currency should be clearly written, such as "RMB 100000.00 Yuan only (RMB one hundred thousand Yuan only)" to prevent the holder of the IOU from tampering. (4) Payment shall be made by bank transfer as far as possible, and the account number and transfer date of the other party may be indicated in the debit note. When handling the transfer, you can indicate the purpose of the loan. If the amount is small, it should be indicated on the IOU that both parties' loans are paid in cash. Either way, the borrower needs to write a receipt for the money received separately. The IOU can only prove that there is a loan contract relationship between the two parties, which is not enough to prove that the borrower has fulfilled the obligation to repay the money. (5) If the borrower is married, it is better to obtain the signature of the spouse, which is more secure for the creditors and prevents one party from refusing to undertake the repayment obligation on the grounds of ignorance or court enforcement, and one party transfers the property to the spouse, resulting in inability to repay. (6) After the IOU is issued, a copy of the borrower's autographed ID card and a copy of the marriage certificate shall be received at the same time. (7) If the amount is large, you can ask a lawyer or a third party to witness the signature. Contents of IOUs The basic contents of IOUs include: creditor's name, loan amount (local and foreign currency), interest calculation, repayment time, liquidated damages (deferred repayment), dispute resolution method, debtor's name, loan date and other elements. As long as you have the creditor's name, loan amount, debtor's name and loan date (although it was added later), it meets the main requirements of the loan, so it has legal effect. Once a dispute arises, it can be used as evidence to claim creditor's rights to the people's court, and the people's court will accept it. For those citizens who do not meet the conditions of bank loans, but encounter a shortage of funds, they can choose to make loan requests to individuals or units with financial ability. After this request is accepted, the borrower may need to write an IOU according to the situation.

Legal basis: Article 490 of the General Principles of the Civil Law states that if the parties conclude a contract in the form of a contract, the contract is established when the parties sign, seal or press their fingerprints. Before signing, sealing or fingerprinting, one party has fulfilled its main obligations, and the contract is established when the other party accepts it. A contract shall be concluded in written form as stipulated by laws, administrative regulations or agreed by the parties. If the parties do not do this in writing, but one party has fulfilled its main obligations and the other party accepts it, the contract is established.