legal ground
Article 69 of the criminal law
If a person commits several crimes before the judgment is pronounced, the execution period shall be decided as appropriate, except for the death penalty and life imprisonment, but the maximum period of public surveillance and criminal detention shall not exceed three years, and the maximum period of fixed-term imprisonment shall not exceed 20 years if it is less than 35 years, and 25 years if it is more than 35 years.
Whoever is sentenced to fixed-term imprisonment or criminal detention for several crimes shall be sentenced to fixed-term imprisonment. Some crimes are sentenced to fixed-term imprisonment and public surveillance, or criminal detention and public surveillance. After the execution of fixed-term imprisonment or criminal detention, public surveillance must still be carried out.
If several crimes are combined, the additional punishment must still be executed. Among them, those with the same kind of supplementary punishment shall be executed jointly, and those with different kinds shall be executed separately.