Legal analysis: the loan contract is a practical contract. If the loan is not actually paid, the contract is invalid. If there is any dispute, it must be clear whether the payment method of funds written in the contract is "cash" or transfer; If it is an IOU, you should pay attention to whether you write "borrowed yuan" or "borrowed yuan" in order to better protect your rights and interests.

Legal basis: Article 679 of the Civil Code of People's Republic of China (PRC), the loan contract between natural persons becomes effective when the lender provides the loan.