There are differences in terms of the types and nature of assignments, and beginning age to serve the country between the
geng and zheng corvée. By geng or geng man is meant a man who serves the country for a month in one year. The two concepts overlap but with emphasis on different aspects of the same thing. Those who must serve in the army according to the law are called zheng , with stress on men′s
service age. And those who are in active service are called zheng men. In contrast, by geng and zheng man are meant not two kinds of men, but different
duties the same person should perform. There is a slight difference in the age of taking geng and zheng corvée. Firstly, a man performs geng duties when he is younger, and zheng duties when he is old and strong enough, according to the law. By this age, he should serve in the army. Within a certain period of one′s life, everyone must be a geng and a zheng man. Geng means one month. Compared with geng, zheng means to serve in the army for one year, and a man should serve in the army for two years altogether.