The receipt should be marked with title, text and signature, in which the title should be marked with "Received"; The text should indicate the name, address, reason, amount and currency of the payee and payer; The signature shall include the payee's signature, date, etc. Article 143 of the Civil Law of People's Republic of China (PRC) is valid if a civil juristic act meets the following conditions: (1) The actor has corresponding capacity for civil conduct; (2) the meaning is true; (three) does not violate the mandatory provisions of laws and administrative regulations, and does not violate public order and good customs. The contents of a contract are agreed upon by the parties, and generally include the following terms: (1) the name and domicile of the parties; (2) Subject matter; (3) quantity; (4) quality; (5) Price or remuneration; (6) Time limit, place and method of performance; (7) Liability for breach of contract; (8) Methods for resolving disputes. The parties may conclude a contract by referring to the model texts of various contracts.