You can't. If a contract is concluded in the form of a public rental housing contract in Tianjin, the contract shall be established when the parties sign, seal or press their fingerprints. If you don't sign the contract, it will be invalid, so the guarantor of Tianjin public rental housing can't sign it. Tianjin, also known as Jingu and Jinmen, is a provincial-level administrative region, municipality directly under the Central Government, national central city and mega-city of People's Republic of China (PRC), and is the economic center of the Bohai Rim region determined by the State Council.