Group 1 - The establishment of a labor relationship occurs from the day the employer starts using the worker, and a written labor contract should be signed within one month from that date [2][4] - According to Article 82 of the Labor Contract Law, if the employer fails to sign a written labor contract within one month to less than one year, they must pay the worker double wages for each month and subsequently sign the written labor contract [5] - If the labor contract expires and the employee continues to work without a new contract, the employer is required to sign a written labor contract, and if this is not done within one month, the employee can claim double wages for the period [6]

Group 1 - The article emphasizes that a written labor contract must be established between the employer and the employee from the start of the employment relationship [3][4] - It is stated that the employer is required to provide a written labor contract upon renewal, and failing to do so is deemed unreasonable [4][10] - The essential clauses that must be included in a labor contract are outlined, including the employer's name, employee's details, contract duration, job responsibilities, working hours, remuneration, social insurance, and other legal requirements [8][11] Group 2 - The article clarifies that a probation period can only be agreed upon once for the same employee in the same company, even if the employee returns to a different position [9] - If an employer fails to sign a written labor contract within one month of employment, they are obligated to pay the employee double wages for each month until a contract is signed, as stipulated by the Labor Contract Law [10][11]