A contract can be modified manually, and it usually needs to be stamped or signed after modification. If the parties enter into a contract in the form of a contract, the contract shall be established when the parties sign, seal or press their fingerprints.

Manual modification of the contract has legal effect. The parties to a contract may change the contract through consultation according to their own wishes. The contents of a contract change must be expressly agreed by the parties concerned and can be changed in writing.