You can't sign labor contracts with acquaintances. The labor contract can only take effect if the employer seals it and the employee signs it. A labor contract shall be reached through consultation between the employer and the employee, and shall come into effect after the text of the labor contract is signed or sealed by the employer and the employee.

Article 16 of People's Republic of China (PRC) Labor Contract Law * * * A labor contract shall come into effect after the employer and the employee reach an agreement through consultation and sign or seal the text of the labor contract. The text of the labor contract is held by the employer and the employee respectively.