Legal basis: Article 511 of the Civil Code of People's Republic of China (PRC). If the parties are unclear about the contents of the relevant contract and cannot be determined according to the provisions of the preceding article, the following provisions shall apply: (1) If the quality requirements are unclear, mandatory national standards shall apply; If there is no mandatory national standard, it shall be implemented in accordance with the recommended national standard; If there is no recommended national standard, it shall be implemented in accordance with industry standards; If there is no national standard or industry standard, it shall be implemented according to the usual standard or the specific standard that meets the purpose of the contract. (2) If the price or remuneration is not clear, it shall be performed according to the market price at the place of performance when the contract is concluded; If government pricing or government-guided pricing should be implemented according to law, it shall be implemented in accordance with the provisions. (3) Where the place of performance is unclear, if money is paid, it shall be performed at the place where the party receiving the money is located; Where real estate is delivered, it shall be performed at the place where the real estate is located; Other targets shall be performed at the place where the party performing the obligations is located. (4) If the time limit for performance is not clear, the debtor may perform at any time, and the creditor may also request performance at any time, but the other party shall be given the necessary preparation time.